cas 1459-20-7, DESYL BENZOATE | Articles data

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An unexpected formation of benzoyl benzoin from benzil during the attempted Knoevenagel type condensation with dimethylmalonate (or malononitrile)
An unexpected product, 2-oxo-1,2-diphenylethyl benzoate (benzoyl benzoin), was isolated during the attempted Knoevenagel reaction of benzil and dimethylmalonate (or malononitrile) in the presence of potassium carbonate. The product was confirmed by spectral analysis as well as by single crystal studies and a mechanism is proposed to explain its formation.
Shyam Sundar,Bedekar, Ashutosh V.
p. 2745 - 2747
(2012)
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Olefin-insertion reaction between the carbonyls of benzils; formation of 1,4-diketones by Michael Additon catalyzed by Cyanide Ion
Benzils (1) react with Michael addition acceptors (2) in the presence of cyanide ion as a catalyst to give 1,4-diketones (3), which are products of ethy lene group insertion between the carhonyls of the benzils. The 1,4-diketones (3) are produced through
Miyashita, Akira,Numata, Atsushi,Suzuki, Yumiko,Iwamoto, Ken-Ichi,Higashino, Takeo
p. 697 - 698
(1997)
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Ionization and Anion-π+ Interaction: A New Strategy for Structural Design of Aggregation-Induced Emission Luminogens
Recent years have witnessed the significant role of anion-π+ interactions in many areas, which potentially brings the opportunity for the development of aggregation-induced emission (AIE) systems. Here, a new strategy that utilized anion-π
Wang, Jianguo,Gu, Xinggui,Zhang, Pengfei,Huang, Xiaobo,Zheng, Xiaoyan,Chen, Ming,Feng, Haitao,Kwok, Ryan T. K.,Lam, Jacky W. Y.,Tang, Ben Zhong
p. 16974 - 16979
(2017)
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Divergent Synthesis of α-Aroyloxy Ketones and Indenones: A Controlled Domino Radical Reaction for Di- A nd Trifunctionalization of Alkynes
Three different modes of aldehyde/alkyne assembly through a controlled radical reaction are devised. While a double C-H activation/annulation leads to indenones, a concurrent oxidation of both aldehydes and alkynes in the course of their connection offers
Jafarpour, Farnaz,Azizzade, Meysam,Golpazir-Sorkheh, Yekta,Navid, Hamed,Rajai-Daryasarei, Saideh
p. 8287 - 8294
(2020/07/15)

Desyl and phenacyl as versatile, photocatalytically cleavable protecting groups: A classic approach in a different (visible) light
A highly efficient, catalytic strategy for the deprotection of classical phenacyl (Pac) as well as desyl (Dsy) protection groups has been developed using visible light photoredox catalysis. The deliberate use of a neutral two-phase acetonitrile/water mixture with K3PO4 applying catalytic amounts of [Ru(bpy)3](PF6)2 in combination with ascorbic acid is the key to this truly catalytic deprotection of Pac- and Dsy-protected carboxylic acids. Our mild yet robust protocol allows for fast and selective liberation of the free carboxylic acids in very good to quantitative yields, while only low catalyst loadings (1 mol %) are required. Both Pac and Dsy, easily introduced from commercially available precursors, can be applied for the direct protection of carboxylic acids and amino acids, offering orthogonality to a great variety of other common protecting groups. We further demonstrate the general applicability and versatility of these formerly underrated protecting groups in combination with our catalytic cleavage conditions, as underscored by the gained high functional group tolerance. Moreover, this method could successfully be adapted to the requirements of solidphase synthesis. As a proof of principle for an efficient visible light, photocatalytic linker cleavage, a Boc-protected tripeptide was split off from commercially available brominated Wang resin.
Speckmeier, Elisabeth,Zeitler, Kirsten
p. 6821 - 6826
(2017/11/06)

Electrogenerated superoxide anion induced oxidative amidation of benzoin
Amide function is very important in both organic and medicinal chemistry. Benzamides can be obtained in good to high yields by reaction of benzoin, primary or secondary amines, molecular oxygen and electrogenerated superoxide anion (obtained with galvanos
Pandolfi, Fabiana,Chiarotto, Isabella,Rocco, Daniele,Feroci, Marta
p. 358 - 367
(2017/10/06)

Bu4NI-Catalyzed α-Oxyacylation of Carbonyl Compounds with Toluene Derivatives
A TBAI (tetrabutylammonium iodide)-catalyzed direct α-oxyacylation of carbonyl compounds from readily available toluene derivatives has been developed. The distinguished features of this metal-free protocol include the employment of simple starting material, a wide carbonyl compound scope, and mild reaction conditions.
Li, Chengliang,Jin, Tao,Zhang, Xinglu,Li, Chunju,Jia, Xueshun,Li, Jian
supporting information
p. 1916 - 1919
(2016/05/19)

Palladium-Catalyzed Chemo- and Enantioselective C?O Bond Cleavage of α-Acyloxy Ketones by Hydrogenolysis
A chemoselective C?O bond cleavage of the ester alkyl side-chain of α-acyloxy ketones was realized for the first time by a highly efficient palladium-catalyzed hydrogenolysis (S/C=6000, the highest catalytic efficiency by far). Furthermore, a kinetic resolution of α-acyloxy ketones was first developed by enantioselective hydrogenolysis with good yields and up to 99 % ee.
Chen, Jianzhong,Zhang, Zhenfeng,Liu, Delong,Zhang, Wanbin
p. 8444 - 8447
(2016/07/19)

Cross-benzoin and Stetter-type reactions mediated by KO: T Bu-DMF via an electron-transfer process
The condensation of aromatic α-diketones (benzils) with aromatic aldehydes (benzoin-type reaction) and chalcones (Stetter-type reaction) in DMF in the presence of catalytic (25 mol%) KOtBu is reported. Both types of umpolung processes proceed with good efficiency and complete chemoselectivity. On the basis of spectroscopic evidence (MS analysis) of plausible intermediates and literature reports, the occurrence of different ionic pathways have been evaluated to elucidate the mechanism of a model cross-benzoin-like reaction along with a radical route initiated by an electron-transfer process to benzil from the carbamoyl anion derived from DMF. This mechanistic investigation has culminated in a different proposal, supported by calculations and a trapping experiment, based on double electron-transfer to benzil with formation of the corresponding enediolate anion as the key reactive intermediate. A mechanistic comparison between the activation modes of benzils in KOtBu-DMF and KOtBu-DMSO systems is also described.
Ragno, Daniele,Zaghi, Anna,Di Carmine, Graziano,Giovannini, Pier Paolo,Bortolini, Olga,Fogagnolo, Marco,Molinari, Alessandra,Venturini, Alessandro,Massi, Alessandro
p. 9823 - 9835
(2016/10/31)

Electron-transfer-initiated benzoin- and Stetter-like reactions in packed-bed reactors for process intensification
A convenient heterogeneous continuous-flow procedure for the polarity reversal of aromatic α-diketones is presented. Propaedeutic batch experiments have been initially performed to select the optimal supported base capable to initiate the two electron-tra
Zaghi, Anna,Ragno, Daniele,Di Carmine, Graziano,De Risi, Carmela,Bortolini, Olga,Giovannini, Pier Paolo,Fantin, Giancarlo,Massi, Alessandro
p. 2719 - 2730
(2017/01/09)

(±)Methanodibenzodiazocine tethered [C-H]δ+ functional site: Study towards benzoin condensation and Baylis-Hillman reactions
Abstract New heterocyclic ring systems consisting of (±) methanodibenzodiazocine and imidazolium/ benzimidazolium salts were synthesized in very good yield. Subsequently, these halide salts were subjected to the anion exchange reaction with KPF6 to yield the corresponding azolium salts in excellent yield. The possible applications of these newly prepared salts were investigated in homogeneous catalysis. Remarkable changes in the catalytic activity were observed by varying the bulkiness of N-substituent at imidazole. Catalytic activity of these newly prepared salts was tested for the benzoin condensation reaction. Exclusive formation of benzoin products were observed in good yield. Similarly, the dimerization of cyclohexen-1-one to Baylis-Hillman type product, 2-(3-oxocyclohexyl)-2-cyclohexen-1-one was studied. [Figure not available: see fulltext.]
Sathyanarayana, Arruri,Prabusankar, Ganesan
p. 821 - 831
(2015/08/06)

Solid-Phase Benzoylation of Phenols and Alcohols in Microwave Reactor: An Ecofriendly Protocol
An efficient solid-phase benzoylation of phenols and alcohols was developed under microwave irradiation. A stoichiometric amount of benzoyl chloride was sufficient to carry out the reaction. This benzoylation features short reaction time, good yields, and easy workup procedures. Furthermore, the scope of the reaction was extended to prepare 3,5-dinitrobenzoyl derivatives of alcohols.
Chakraborty, Suchandra,Saha, Ahana,Basu, Kaushik,Saha, Chandan
supporting information
p. 2331 - 2343
(2015/10/12)

Molecular modeling based approach, synthesis, and cytotoxic activity of novel benzoin derivatives targeting phosphoinostide 3-kinase (PI3Kα)
Abstract The oncogenic potential of phosphatidylinositol 3-kinase (PI3Kα) has made it an attractive target for anticancer drug design. In this work, we describe our efforts to optimize the lead PI3Kα inhibitor 2-hydroxy-1,2-diphenylethanone (benzoin). A s
Sabbah, Dima A.,Saada, Musaab,Khalaf, Reema Abu,Bardaweel, Sanaa,Sweidan, Kamal,Al-Qirim, Tariq,Al-Zughier, Amani,Halim, Heba Abdel,Sheikha, Ghassan Abu
supporting information
p. 3120 - 3124
(2015/07/08)

Beyond benzoin condensation: Trimerization of aldehydes via metal-free aerobic oxidative esterification of aldehydes with benzoin products in the presence of cyanide
An unusual trimerization of aldehydes in the presence of cyanide via metal-free aerobic oxidative esterification under ambient conditions is described. Various aromatic aldehydes provided the corresponding oxidative esterification products in good to excellent yields. Mechanistic studies suggested that this reaction would proceed via a two-step sequence: cyanide-catalyzed benzoin condensation of aldehydes and subsequent aerobic oxidative esterification of aldehydes with the resultant benzoin products. The usefulness of this protocol was further demonstrated by converting the resulting trimeric products into other biologically important compounds.
Kim, Yoo-Jin,Kim, Na Yeun,Cheon, Cheol-Hong
p. 2514 - 2517
(2014/05/20)

Benzoin condensation and stetter reaction catalysed by N,N-dimethylbenzimidazolium iodide in [Bmim][OH]
N,N-Dimethylbenzimidazolium iodide catalysed benzoin condensation and Stetter reaction in 1-butyl-3-methylimidazolium hydroxide [bmim][OH] which acts as a basic catalyst as well as a solvent for the reactions are described. The recycled reaction media containing benzimidazolium salt can be reused for several times without significant loss of efficiency.
Phungpis, Baramee,Hahnvajanawong, Viwat,Theramongkol, Parinya
p. 933 - 939
(2015/02/19)

Aerobic oxidation of NHC-catalysed aldehyde esterifications with alcohols: Benzoin, not the Breslow intermediate, undergoes oxidation
Benzoin (and neither the Breslow intermediate nor the NHC-aldehyde tetrahedral adduct) has been unambiguously identified as the oxidised species in aerobic NHC-catalysed aldehyde esterifications.
Delany, Eoghan G.,Fagan, Claire-Louise,Gundala, Sivaji,Zeitler, Kirsten,Connon, Stephen J.
p. 6513 - 6515
(2013/07/26)

Methylsulfinyl (Dimsyl) anion as umpolung catalyst for the chemoselective cross-benzoin reaction of α-diketones with aldehydes
The hitherto unreported ability of the methylsulfinyl carbanion (dimsyl anion) to generate acyl anion equivalents is described. The dimsyl anion, in fact, efficiently catalyzes chemoselective intermolecular cross-benzoin condensations of diaryl α-diketones (benzils) with various aromatic and aliphatic aldehydes to give the corresponding aryl-aryl and aryl-alkyl benzoin benzoates in an atom-economic fashion. The dimsyl anion acts as an environmentally friendly alternative to the toxic cyanide anion and it is obtained by in situ deprotonation of dimethyl sulfoxide (DMSO) solvent with a catalytic amount of a strong base, potassium tert-butoxide (t-BuOK) the optimal promoter. The assumption that the methylsulfinyl carbanion is the active catalyst in the title transformation is supported by electrospray ionization mass spectrometry (ESI-MS) experiments. Copyright
Bortolini, Olga,Fantin, Giancarlo,Ferretti, Valeria,Fogagnolo, Marco,Giovannini, Pier Paolo,Massi, Alessandro,Pacifico, Salvatore,Ragno, Daniele
p. 3244 - 3252
(2013/12/04)

ANTI-BIOFILM COMPOUNDS
The present invention provides non-peptide compounds of formula (I) wherein: X is -(C1-C8)allcyl-, aryl or -aryl(C1-C8)alkyl-; Y is -(C1-C8)alkyl- or absent; W is heteroaryl, (C3-C7)carbocycle or aryl, wherein any heteroaryl, (C3-C7)carbocycle or, aryl of W is optionally substituted with one or more (e.g. 1, 2, 3, 4 or 5) Z1 groups; R1 is (C1-C8)alkyl, (C2-C8)alkenyl, (C2-C8)alkynyl or aryl, wherein aryl is optionally substituted with one or more (e.g. 1, 2, 3, 4 or 5) groups selected from (C1-C8)alkyl, (C2-C8)alkenyl, (C2-C8)alkynyl, (C3-C7)carbocycle, halo(C1-C3)alkyl, -CN, NO2, halogen, -ORa, -SRa, -S(O)2NRbRc, -NRbRc, -NRaCORd, -C(O)Ra, -C(O)ORa, and -C(O)NRbRc; R2 is (C1-C8)alkyl, (C2-C8)alkenyl, (C2-C8)Jalkynyl or aryl, wherein aryl is optionally substituted with one or more (e.g. 1, 2, 3, 4 or 5) groups selected from (C1-C8)alkyl, (C2-C8)alkenyl, (C2-C8)alkynyl, (C3-C7)carbocycle, halo(C1-C3)alkyl, -CN, NO2, halogen, -ORe, -SRe, -S(O)2NRfRg, -NRfRg -NReCORh, -C(O)Re, -C(O)ORe and -C(O)NRfRg; I that mimic the streptococcal; SspB Adherence Region (BAR) and function as inhibitors of P. gingivalis adherence to streptococci. The invention also provides methods of making and using the inhibitors.
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(2013/03/26)

In situ generated (Hypo)iodite catalysts for the direct α-oxyacylation of carbonyl compounds with carboxylic acids
It′s the iodine: The intra- and intermolecular title reaction is catalyzed by an in situ generated ammonium (hypo)iodite species. Either H 2O2 or tert-butyl hydroperoxide (TBHP) can be used as an environmentally benign oxidant and a wide range of substrates react to give the corresponding α-acyloxycarbonyl compounds in good to excellent yields.
Uyanik, Muhammet,Suzuki, Daisuke,Yasui, Takeshi,Ishihara, Kazuaki
supporting information; experimental part
p. 5331 - 5334
(2011/07/08)

An organocatalytic ionic liquid
The carbene concentration in 1-ethyl-3-methylimidazolium-acetate ionic liquid is sufficiently high to act as a catalyst in benzoin condensation, hydroacylation and also in oxidation of an alcohol by using CO2 and air. This observation reveals the potential of ionic liquid organocatalysts, uniting the beneficial properties of these two families of compounds.
Kelemen, Zsolt,Holloczki, Oldamur,Nagy, Jozsef,Nyulaszi, Laszlo
supporting information; experimental part
p. 5362 - 5364
(2011/09/13)

Metal-free reductive cleavage of C-O σ-bonds in acyloin derivatives by an organic neutral super-electron-donor
(Chemical Equation Presented) Neutral organic electron-donor 7, formally a pyridinylidene carbene dimer, effects reductive cleavage of C-O σ-bonds in acyloin derivatives Ar(CO)CRR′OX (X = OAc, OPiv, OBz, OMs) and this represents the first cleavage of C-O σ-bonds by a neutral organic electron-donor. The methodology is applicable to a large array of substrates and the reduced counterparts were isolated in good to excellent yields. For certain substrates, donor 7 behaves as a base, effecting condensation reactions with some acetate ester derivatives of acyloins, leading to butenolides. The variation in reactivity among the different substrates was rationalized. 2009 American Chemical Society.
Cutulic, Sylvain P. Y.,Findlay, Neil J.,Zhou, Sheng-Ze,Chrystal, Ewan J. T.,Murphy, John A.
experimental part
p. 8713 - 8718
(2009/12/28)

Synthesis of multisubstituted furans, pyrroles, and thiophenes via ynolates
An efficient synthetic method for the preparation of multisubstituted furans, thiophenes, and pyrroles using ynolates was developed. This novel formal [4 + 1] annulation by C2-C3 and C3-C4 bond formations Includes cycloaddition, cyclization, decarboxylati
Shindo, Mitsuru,Yoshimura, Yutaka,Hayashi, Maiko,Soejima, Hiroe,Yoshikawa, Takashi,Matsumoto, Kenji,Shishido, Kozo
p. 1963 - 1966
(2008/02/02)

Hydroacylation of activated ketones catalyzed by N-heterocyclic carbenes
N-heterocyclic carbenes derived from triazolium salts are effective catalysts between 10 and 15 mol % for the hydroacylation of activated ketones. The reducing equivalent is generated via the interaction of a nucleophilic carbene species and an aromatic aldehyde. The subsequent alcohol product can undergo an acylation event with the resulting acyl heteroazolium intermediate formed in situ between the NHC and the aldehyde. This unprecedented multiple bond-forming reaction can accommodate aromatic aldehydes as the hydride source and various electron-deficient ketones. Preliminary mechanistic evidence indicates that the reduction and acylation steps are sequential operations. The intramolecular variant of this organocatalytic reaction affords benzofuranones in good yield. Copyright
Chan, Audrey,Scheidt, Karl A.
p. 4558 - 4559
(2007/10/03)

Zinc oxide (ZnO) as a new, highly efficient, and reusable catalyst for acylation of alcohols, phenols and amines under solvent free conditions
Zinc oxide (ZnO) is a highly efficient catalyst for the acylation of a variety of alcohols, phenols and amines with acid chlorides or acid anhydrides under solvent free conditions. Primary, secondary, tertiary, allylic and benzylic alcohols, diols and phenols with electron donating or withdrawing substituents can be easily acylated in good to excellent yield.
Hosseini Sarvari, Mona,Sharghi, Hashem
p. 10903 - 10907
(2007/10/03)

Reactions of aroyl chlorides with samarium metal in DMF-controllable syntheses of O-aroylbenzoins, 1,2-diarylethanones, and (z)-α, α′-stilbenediol dibenzoates
Reduction of aroyl chlorides carried out in DMF with samarium metal has been studied. Samarium metal, which requires not any intended activation or pretreatment, was found to react with aroyl chloride in a controllable manner. Correspondingly, O-aroylbenzoins, 1,2-diarylethanones, or (Z)-α, α′-stilbenediol dibenzoates were afforded as the major products under controlled conditions.
Liu, Yongjun,Wang, Xiaoxia,Zhang, Yongmin
p. 4009 - 4022
(2007/10/03)

Efficient and selective conversion of trimethylsilyl and tetrahydropyranyl ethers to their corresponding acetates and benzoates catalyzed by bismuth(III) salts
A variety of TMS and THP ethers are efficiently converted to their corresponding acetates and benzoates with acetic and benzoic anhydrides in the presence of catalytic amounts of Bi(III) salts such as BiCl3, Bi(TFA)3, and Bi(OTf)sub
Mohammadpoor-Baltork, Iraj,Khosropour, Ahmad R.
p. 189 - 193
(2007/10/03)

Reactivity of the electrogenerated O2·-/CO2 system towards alcohols
The reactivity towards alcohols of the system obtained from the reduction of dioxygen carried out in aprotic dipolar solvents and in the presence of carbon dioxide has been investigated. This reagent is able to convert primary and secondary alcohols into the corresponding aldehydes and ketones. The optimization of the experimental conditions as well as the advantages and the limitations of the method are reported. Wiley-VCH Verlag GmbH, 2001.
Casadei, Maria Antonietta
p. 1689 - 1693
(2007/10/03)

Bismuth(III) salts as convenient and efficient catalysts for the selective acetylation and benzoylation of alcohols and phenols
Efficient acetylation and benzoylation of alcohols and phenols with acetic and benzoic anhydrides have been carried out under catalysis of bismuth(III) salts including BiCl3, Bi(TFA)3 and Bi(OTf)3. Selective acetylation and benzoylation of alcohols in the presence of phenols is an additional advantage of this procedure.
Mohammadpoor-Baltork, Iraj,Aliyan, Hamid,Reza Khosropour, Ahmad
p. 5851 - 5854
(2007/10/03)

Base-induced rearrangement of O-benzoylbenzaldehyde cyanohydrin to benzil and the further reactions of benzil
O-Benzoylbenzaldehyde cyanohydrin has been found to form benzil in DMF in a base-catalysed reversible reaction. The possibility of using the reaction for the synthesis of unsymmetrical benzils from an aldehyde derivative and an acid derivative was investigated, but such a synthesis was made invalid by the further reaction of benzil with strong bases. The reaction of benzil with potassium tertbutoxide in DMF gave several products, among which the formation of two of them involved the anion of DMF and the formation of others included redox reactions. Acta Chemica Scandinavica 1998.
Zheng, Zi-Rong,Kjaer, Niels Them,Lund, Henning
p. 362 - 365
(2007/10/03)

Convenient syntheses of 2-alkyl(Aryl)-4,5-diphenyloxazoles and 2-alkyl(Aryl)-4-phepyloxazoles
The synthetic methods to prepare 2-alkyl(aryl)-4,5-diphenyloxazoles and 2-alkyl(aryl)-4-phenyloxazoles were improved on the basis of a mechanistic study of oxazole formation from α-hydroxy ketones (carboxylic esters of benzoin and phenacyl alcohols). By these methods, seven trisubstituted oxazoles and twelve disubstituted oxazoles of the title compounds were prepared.
Pei, Weiwei,Li, Shaohui,Nie, Xiaoping,Li, Yiwei,Pei, Jian,Chen, Bingzi,Wu, Jie,Ye, Xiulin
p. 1298 - 1304
(2007/10/03)

The reduction of α-silyloxy ketones using phenyldimethylsilyllithium
Phenyldimethylsilyllithium reacts with acyloin silyl ethers RCH(OSiMe3)COR 8 to give regiodefined silyl enol ethers RCH=C(OSiMe2Ph)R 9, and hence by hydrolysis ketones RCH2COR 10. The yields can be high but are usually moderate. The mechanism of this reduction is established to involve a Brook rearrangement (Scheme 6) rather than a Peterson elimination (Scheme 1). Although the mechanism appears to be the same in each case, the stereochemistries of the silyl enol ethers 9 are opposite in sense in the aromatic series (R = Ph, Scheme 7) and the aliphatic series (R = cyclohexyl, Scheme 8), with the major aromatic silyl enol ether being the thermodynamically less stable isomer E-PhCH=C(OSiMe2Ph)Ph E-9aa, and the major aliphatic silyl enol ether being the thermodynamically more stable isomer Z-c-C6H11CH= C(OSiMe2Ph)-c-C6H11 Z-9ba. This is a consequence of anomalous anti-Felkin attack in the aromatic series. The reaction with the silyl ether ButCH(OSiMe3)COPh 13b is normal in giving Z-ButCH= C(OSiMe2Ph)Ph Z-38 (Scheme 11), but reduction of the silyl ether 8a with lithium aluminium hydride is also anti-Felkin giving with high selectivity the meso diol PhCH(OH)CH(OH)Ph 39. The reaction between Phenyldimethylsilyllithium and the acyloin silyl ether 8d (R = But) does not give the ketone ButCH2COBut, but gives instead the anti-Felkin meso diol ButCHOHCHOHBut 40 also with high selectivity (Scheme 12). Silyllithium and some related reagents react with trifluoromethyl ketones 46 and 48 to give α,α-difluoro silyl enol ethers 47 and 49 (Scheme 14).
Fleming, Ian,Roberts, Richard S.,Smith, Stephen C.
p. 1215 - 1228
(2007/10/03)

Catalytic action of azolium salts. VIII. Oxidative aroylation with arenecarbaldehydes catalyzed by 1,3-dimethylbenzimidazolium iodide
Refluxing of a mixture of benzaldehyde (1a), 1,3- dimethylbenzimidazolium iodide (7), p-nitroaniline (9b) as an oxidizing agent, and 1,8-diazabicyclo[5,4,0]-7-undecene (DBU) in MeOH afforded methyl benzoate (2a) in good yield. Other methyl arenecarboxylates 2 were similarly obtained from arenecarbaldehydes 1. We showed that this aroylation proceeds via the 2-aroyl-1,3-dimethylbenzimidazolium salt (8). The 1,2,4-triazolium salt (18) and the naphtho[1,2-d]imidazolium salt (19) were also effective catalysts for this oxidative aroylation. However, the aroylation did not proceed with the imidazolium salt (20). In the presence of flavins (25a - c), arenecarbaldehydes 1 reacted in MeOH under aerobic conditions catalyzed by the benzimidozolium salt 7 to give the corresponding methyl arenecarboxylates 2. 1-Methyl-3-[3-(10-phenylisoalloxazin-3-yl)propyl]benzimidazolium bromide (27) is an effective complex catalyst for this oxidative aroylation.
Miyashita, Akira,Suzuki, Yumiko,Nagasaki, Izuru,Ishiguro, Chie,Iwamoto, Ken-Ichi,Higashino, Takeo
p. 1254 - 1258
(2007/10/03)

Titanium-Induced Syntheses of Furans, Benzofurans and Indoles
Highly reactive titanium on graphite as the reagent of choice promotes intramolecular McMurry type reactions of acyloxy- and acylamido carbonyl compounds affording furans, benzofurans and indoles in good to excellent yields.A variety of reducible groups in the substrates is tolerated (e.g. -F, -Cl, -Br, -I, -CF3, -OMe, -CN, -thiophenyl, -COOR, -CONR2) and strained products such as 11h can be obtained, the X-ray analysis of which is reported.The experimental results indicate the possible formation of dianions from the aromatic aldehydes or ketones as reactive intermediates which attack the ester or amide functions in their proximity, rather than a radical path via ketyls.
Fuerstner, Alois,Jumbam, Denis N.
p. 5991 - 6010
(2007/10/02)

X-RAY CRYSTAL STRUCTURE AND REACTIONS OF 2-CYANO-1,3-DIBENZOYL-2,3-DIHYDROBENZIMIDAZOLE, A NOVEL REISSERT COMPOND
The X-ray crystal structure analysis and energetically favoured conformation calculated by the MM2 method for the new, novel benzimidazole Reissert compond 1 are reported.A highly delocalized and very stable carbanion is interpreted by resonance structures.Interesting reactions of compound 1 are discussed.
Jois, Yajnanarayana H. R.,Berg, Michael A. G.,Merola, Joseph S.,Gibson, Harry W.
p. 2997 - 3000
(2007/10/02)

Studies on pyrazolo[3,4-d]pyrimidine derivatives. XVII. Reactions of 5-benzoyl-4,5-dihydro-6-methyl-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4- carbonitrile (The 6-methylpyrazolopyrimidine Reissert compound)
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Miyashita,Sato,Taido,Tanji,Oishi,Higashino
p. 230 - 233
(2007/10/02)

Reissert Compound Formation with Fused Five-Membered Ring Heterocycles
Reissert compounds have been prepared in high yield from benzothiazole by use of trimethylsilyl cyanide as source of cyanide in a single phase system.Analogues have been made from benzoxazole, indazole and 1-methylindazole but the method was unsuccessful with 1,2-benzisoxazole and pyrazole.Conjugate base alkylation followed by removal of the Reissert grouping provides a route to 2-alkylbenzothiazoles and -benzoxazoles, and 3-alkylated indazoles.Efficient access to pyridobenzothiazole and benzothiazoloisoquinoline derivatives results from appropriate intramolecular cyclisations.A crystal structure determination of 3-benzoyl-2,3-dihydro-2-benzothiazolecarbonitrile is reported.
Uff, Barrie C.,Ho, Yee-Ping,Brown, David S.,Fisher, Ian,Popp, Frank D.,Kant, Joydeep
p. 2652 - 2681
(2007/10/02)

Reissert Compound Studies. LXI. Preparation and Reactions of Quinazoline Di-Reissert Compounds
Various di-Reissert compounds and analogs were prepared from quinazoline by use of trimethylsilyl cyanide together with a catalytic amount of anhydrous aluminum chloride.Reactions of these quinazoline di-Reissert compounds are reported.
Hahn, Jung-Tai,Popp, Frank D.
p. 1357 - 1372
(2007/10/02)

Purines. VIII. Reactions of 1-Benzoyl-1,6-dihydro-9-phenyl-9H-purine-6-carbonitrile (9-Phenylpurine Reissert Compound) with Acid, Bases, and Electrophiles
1-Benzoyl-1,6-dihydro-9-phenyl-9H-purine-6-carbonitrile (1, 9-phenylpurine Reissert compound) was hydrolyzed in an acid medium to give the ring fission product of the pyrimidine ring (3, 4).Alkaline hydrolysis of 1 gave 9-phenyl-9H-purine (2) and benzoic acid (5).The anion of 1 generated from 1 and sodium hydride in tetrahydrofuran underwent aromatization, resulting in the formation of 9-phenyl-9H-purine-6-carbonitrile (6) together with 2.The reaction of 1 with aromatic aldehydes in the presence of sodium hydride proceeded to give the 6-purinylmethyl benzoates (8a-c), together with 2 and 9.On the other hand, the reaction of 1 with 2,4-dinitrochlorobenzene in the presence of sodium hydride failed to give the corresponding 6-arylpurine, and the aromatization product 6 was obtained.Keywords - 9H-purine; Reissert compound anion; 9H-purin-6-ylmethyl benzoate
Tanji, Ken-ichi,Sato, Susumu,Miyashita, Akira,Oishi, Etsuo,Higashino, Takeo
p. 187 - 189
(2007/10/02)

Equilibria among Anions α-Hydroxy β-Diketones and α-Ketol Esters
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Rubin, Mordecai B.,Inbar, Shai
p. 3355 - 3358
(2007/10/02)

Reactions of 3-Benzoyl-3,4-dihydro-2-methyl-4-quinazolinecarbonitrile (2-Methylquinazoline Reissert Compound) with Acid, Base, Sodium Hydride, and Electrophiles
Acid hydrolysis of 3-benzoyl-3,4-dihydro-2-methyl-4-quinazolinecarbonitrile (11, 2-methylquinazoline Reissert compound) resulted in the formation of the oxazole (13).Alkaline hydrolysis gave 2-methylquinazoline (12) and banzoic acid (8).The anion (D1), generated from 11 and NaH in dimethylformamide (DMF), underwent decomposition to give the ketone (14) and the cyanoquinazoline (15) together with by-products 12 and O-benzoylbenzoin (9).Compound 11 reacted with aromatic aldehydes (10a-c) in the presence of NaH to give the benzoates (16a-c) and by-products 12 and 15.Alkylation (or arylation) with alkyl (or aryl) halides (11a, b) afforded the corresponding 4-substituted derivatives (19a, b) and a by-product 14.The reactivities of 11 and 3-benzoyl-3,4-dihydro-4-quinazolinecarbonitrile (21, quinazoline Reissert compound) are compared. Keywords---Reissert compound; quinazoline; hydrolysis; Reissert compound anion; rearrengement; aromatization; electronic effect; electrophilic substitution
Higashino, Takeo,Sato, Susumu,Suge, Hiroki,Tanji, Ken-Ichi,Miyashita, Akira,Katori, Tatsuhiko
p. 930 - 939
(2007/10/02)

A New Site Selective Synthesis of Benzoin Esters. Synthesis of Symmetrically and Unsymmetrically Substituted Benzils
A series of novel benzoin esters has been obtained in high yield, in a site selective synthesis, by the acid hydrolysis of a series of 4-benzoyloxy-2-azabuta-1,3-dienes.The oxidation of the benzoin esters allows the preparation of symmetrically and unsymmetrically substituted benzils by a route that is superior, in some cases, to those previously reported.
Armesto, Diego,Horspool, William M.,Ortiz, Maria J.,Perez-Ossorio, Rafael
p. 799 - 801
(2007/10/02)

O-Acylation of α-Diazo Ketones. A Novel Route to Alkenediazonium and 1,3-Dioxolium Salts
O-Acylation of α-diazo ketones with benzoyl triflate or diphenylacetyl triflate generates the corresponding β-(acyloxy)alkenediazonium salts 5 and 15.These thermolabile compounds can be trapped with isopropylamine at low temperature to give triazoles 21.Dediazoniation of 5 and 15 leads to 1,3-dioxolium salts 7 and 16 as well as small amounts of vinyl triflates 8 and 17 via intermediary vinyl cations.O-Benzoylation with benzoyl triflate has also been realized for the quinoid α-diazo ketone 9; the resulting diazonium salt 10 gives triazole 13 on treatment with isopropylamine.
Lorenz, Wolfgang,Maas, Gerhard
p. 375 - 381
(2007/10/02)

Studies on Pyrazolopyrimidine Derivatives. XV. Reactions Involving the Formation of the Anion of the Reissert Compound Derived form 1H-Pyrazolopyrimidine
The anion (A) of the Reissert compound (1, 5-benzoyl-4,5-dihydro-1-phenyl-1H-pyrazolopyrimidine-4-carbonitrile) was found to react with electrophiles in two ways.One is nucleophilic attack of the anion A.The other is self-decomposition of the anion A.Thus, A underwent nucleophilic attack with aromatic and aliphatic aldehydes (4a-j), resulting in the formation of the corresponding α-aryl (or alkyl)-1-phenyl-1H-pyrazolopyrimidin-4-ylmethyl benzoates (6a-j) together with 1-phenyl-1H-pyrazolopyrimidine (2), the 4,4'-dimer (7) of 2, O-benzoylaroins (8a-d), and O-benzoylcyanohydrins (9e-j).Nucleophilic substitution took place in the reaction of A with 2,4-dinitrochlorobenzene (14a) and methyl iodide (14d), giving the 4-(2,4-dinitrophenyl) derivative (17a) of 2 and 5,7-dibenzoyl-4-methyl-1-phenyl-4-(1-phenyl-1H-pyrazolopyrimidin-4-yl)-4,5,6,7-tetrahydro-1H-pyrazolopyrimidine-6-carbonitrile (19), respectively.However, the anion A did not react with other aryl (or alkyl) halides (14b, c, e), ketones (11a, b), 2-alkenonitriles (21a, b), and dimethylacetylenedicarboxylate (22), and underwent the known self-decomposition, resulting in the formation of products such as 2, 7, the cyano derivative (18) of 2, and the ester 6a.Keywords - pyrazolopyrimidine; Reissert compound; aldehyde; aryl halide; nucleophilic attack; self-decomposition; pyrazolopyrimidinemethanol
Hagishino, Takeo,Sato, Susumu,Miyashita, Akira,Katori, Tatsuhiko
p. 4078 - 4086
(2007/10/02)

ANIONIC ACTIVATION BY FLUORIDE ION IN SOLID-LIQUID SYSTEMS. SYNTHESIS OF 3 (2H)-FURANONES AND 2 (5H)-FURANONES.
The evolution of 2-acyloxy 2-methyl 3-oxobutanamides 1 and 2-acyloxy 3-oxo 2,3-diphenylpropanamides 13 under anionic activation by cesium fluoride was studied.The fluoride ion is an efficient base for the heterocyclization of 1 into 3 (2H)-furanones and 2 (5H)-furanones, but the hydrolysis of the ester group lowered the selectivity of the reaction.However, the cleavage of 13 into the esters 14 and the cyclization of 3-benzoyloxy 3-methyl 2-butanone into bullatenone are very selective.
Sebti, S.,Foucaud, A.
p. 1361 - 1368
(2007/10/02)

Aroylation of Carbanions Derived from N-(Diphenylmethyl)arylmethanimines. A Synthesis of 4-Aroyloxy-2-azabuta-1,3-dienes
The acylation of carbanions derived from N-(diphenylmethyl)arylmethanimines using aroyl chlorides, allows the preparation of a new type of substituted 2-azabuta-1,3-dienes in which the imino group is conjugated with an enol ester.The reaction is quite general and facilitates the preparation of a wide range of 2-azadienes with electron-donating and electron-withdrawing groups on the phenyl rings.The site selectivity for the attack of the electrophile on the aza-allyl anion can be controlled by the substituents on the carbanion and on the hardness of the electrophile.
Armesto, Diego,Ortiz, Maria J.,Perez-Ossorio, Rafael
p. 2021 - 2026
(2007/10/02)

Synthesis of Nitrogen Heterocycles by Condensation of the Conjugate Base of Open-Chain Reissert Compound Analogs with Vinyltriphenylphosphonium Bromide (Schweizer's Salt)
Reaction of the conjugate base of several open-chain Reissert compound analogs with vinyltriphenylphosphonium bromide is shown to afford a convenient route to substituted pyrroles.The condensation is a two-step process involving an initial reversible addition to form an unstabilized Wittig reagent followed by an intramolecular Wittig reaction upon the carbonyl group of the tertiary amide functionality with concomitant elimination of HCN.Several applications to the synthesis of 1,2,5-trisubstituted pyrroles are presented, together with attempts to expand this methodology to the synthesis of other heterocyclic systems.
Cooney, John V.,Beaver, Bruce D.,McEwen, William E.
p. 635 - 642
(2007/10/02)

Reactions of the Anion of Quinazoline Reissert Compound (3-Benzoyl-3,4-dihydro-4-quinazolinecarbonitrile) with Electrophiles
Reactions of the quinazoline Reissert compound (2) with various electrophiles in the presence of sodium hydride in N,N-dimethylformamide were investigated.The reactions with aldehydes (3) and ketones (12) gave α-aryl (or alkyl)-(7) and α-alkyl-α-aryl (or alkyl)-4-quinazolinylmethyl benzoates (16), respectively.The reaction with ?-deficient heteroaromatics (10a-c) gave 4-heteroarylquinazolines (20a-c).Alkylation (or arylation) with alkyl (or aryl) halides (23a-c) afforded 4-substituted 3-benzoyl-3,4-dihydro-4-quinazolinecarbonitriles (24a-c).The reaction with dimethyl acetylenedicarboxylate proceeded in two ways, giving dimethyl 3-phenylpyrroloquinazoline-1,2-dicarboxylate (27) and dimethyl 3-benzoyl-4-cyano-1,2,3,4-tetrahydro-2,4-ethenoquinazoline-9,10-dicarboxylate (28).The reaction with 2-alkenonitriles (29a,b) resulted in the formation of 2-benzoyl-3-(4-quinanolinyl)alkanonitriles (32a,b).Keywords - rearrangement; substitution; 1,3-dipolar addition; quinazoline Reissert compound anion; α-substituted 4-quinazolinylmethyl benzoate; 4-heteroarylquinazoline; 4-substituted 3,4-dihydro-4-quinazoline carbonitrile; pyrroloquinazoline; 2,4-ethenoquinazoline; 2-benzoyl-3-(4-quinazolinyl)alkanonitrile
Higashino, Takeo,Kokubo, Hiroyasu,Hayashi, Eisaku
p. 950 - 961
(2007/10/02)

PREPARATION AND REACTIONS OF 3-BENZOYL-3,4-DIHYDRO-4-QUINAZOLINECARBONITRILE (QUINAZOLINE REISSERT COMPOUND)
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Higashino, Takeo,Kokubo, Hiroyasu,Hayashi, Eisaku
p. 512
(2007/10/02)

Preparation and Reactions of Quinazoline Reissert Compound (3-Benzoyl-3,4-dihydro-4-quinazolinecarbonitrile)
The benzoylation of 3,4-dihydro-4-quinazolinecarbonitrile (3) with benzoyl chloride in pyridine gave quinazoline Reissert compound (1, 3-benzoyl-3,4-dihydro-4-quinazolinecarbonitrile) in 82percent yield. The alkaline hydrolysis of 1 in methanol resulted in the formation of quinazoline (2) and benzoic acid (4).Acid hydrolysis gave 2-benzamido-2-(2-aminophenyl)acetonitrile (6), 4, and 2.The HCl salt of 1 existed predominantly in the cyclic amidinium structure of the type 8.Compound 1reacted with sodium hydride in dimethylformamide to yield 4-quinazolinecarbonitrile (9), α-phenyl-4-quinazolinylmethyl benzoate (10) and O-benzoylbenzoin (11). In the present paper we compare the chemical properties of 1 with those of isoquinoline Reissert compound (13, 2-benzoyl-1,2-dihydro-1-isoquinolinecarbonitrile). Keywords --- quinazoline Reissert compound; cyclic amidinium cation; alkaline hydrolysis; acid hydrolysis; quinazoline Reissert compound anion; acetonitrile derivative; 4-quinazolinecarbonitrile; 4-quinazolinylmethyl benzoate derivative
Higashino, Takeo,Kokubo, Hiroyasu,Hayashi, Eisaku
p. 3900 - 3905
(2007/10/02)

PHOTODEUTERUNG VON BENZALDEHYD UND SUBSTITUIERTEN BENZALDEHYDEN
In the presence of deuterium oxide benzaldehyde (1a) and substituted benzaldehydes likewise possessing lowest triplet states of (n,?*) character yield formyl-deuteriated benzaldehydes by fast and efficient photoreactions.Quantum yields of formation of 7-deuterio benzaldehyde (1b) in solvent acetonitrile-deuterium oxide 3:1 are 0.57 at 313 nm, 0.54 at 334 nm, 0.62 at 365 nm, and in acetone-deuterium oxide 3:1 0.87 at 313 nm, 0.83 at 334 nm and 0.91 at 365 nm.By products, mainly meso- and dl-dihydrobenzoin and benzoin, are formed to a small extent only.On the basis of CIDNP measurements the mechanism of photodeuteriation is discussed.
Defoin, Albert,Defoin-Straatmann, Rosalie,Kuhn, Hans Jochen
p. 2651 - 2662
(2007/10/02)