- Rh-Catalyzed Coupling of Aldehydes with Allylboronates Enables Facile Access to Ketones
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We present herein a novel strategy for the preparation of ketones from aldehydes and allylic boronic esters. This reaction involves the allylation of aldehydes with allylic boronic esters and the Rh-catalyzed chain-walking of homoallylic alcohols. The key to this successful development is the protodeboronation of alkenyl borylether intermediate via a tetravalent borate anion species in the presence of KHF2 and MeOH. This approach features mild reaction conditions, broad substrate scope, and excellent functional group tolerance. Mechanistic studies also supported that the tandem allylation and chain-walking process were involved.
- Zhang, Kezhuo,Huang, Jiaxin,Zhao, Wanxiang
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supporting information
(2022/02/21)
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- Chemoselective reduction of ?,￠-unsaturated carbonyl and carboxylic compounds by hydrogen iodide
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The selective reduction of ?,￠-unsaturated carbonyl compounds was achieved to produce saturated carbonyl compounds with aqueous HI solution. The introduction of an aryl group at an ? or ￠ position efficiently facilitated the reduction with good yield. The reaction was applicable to compounds bearing carboxylic acids and halogen atoms. Through the investigation of the reaction mechanism, it was found that Michael-type addition of iodide occurred to produce ￠-iodo compounds followed by the reduction of C-I bond via anionic and radical paths.
- Matsumoto, Shoji,Marumoto, Hayato,Akazome, Motohiro,Otani, Yasuhiko,Kaiho, Tatsuo
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p. 590 - 599
(2021/03/29)
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- Facile preparation of 5-alkyl-1-aryltetrazoles with arenes, acyl chlorides, hydroxylamine, and diphenylphosphoryl azide
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Successive treatment of arenes with acyl chlorides and AlCl3, the addition of water and removal of solvent, the reaction with NH2OH?HCl and K2CO3, and the reaction with diphenylphosphoryl azide and DBU under warming conditions gave the corresponding 5-alkyl-1-aryltetrazoles efficiently in good to moderate yields. The present method is one-pot transformation of arenes into 5-alkyl-1-aryltetrazoles using the Friedel-Crafts acylation and the Beckmann rearrangement under transition-metal-free conditions.
- Shibasaki, Kaho,Togo, Hideo
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p. 1816 - 1830
(2020/11/19)
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- Iridium-Catalyzed Asymmetric Hydrogenation of α-Fluoro Ketones via a Dynamic Kinetic Resolution Strategy
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The discrimination of a fluorine atom from a hydrogen atom has been challenging in asymmetric catalysis. We herein report iridium-catalyzed hydrogenation of α-fluoro ketones using a strategy of dynamic kinetic resolution. Both enantiomeric and diastereomeric selectivities were satisfactory in the preparation of β-fluoro alcohols. The DFT calculation revealed a C-F···Na charge-dipole interaction in the transition state of hydride transfer. This noncovalent interaction would be responsible for the diastereomeric control.
- Tan, Xuefeng,Wen, Jialin,Zeng, Weijun,Zhang, Xumu
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supporting information
p. 7230 - 7233
(2020/10/02)
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- Additive-Free Isomerization of Allylic Alcohols to Ketones with a Cobalt PNP Pincer Catalyst
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Catalytic isomerization of allylic alcohols in ethanol as a green solvent was achieved by using air and moisture stable cobalt (II) complexes in the absence of any additives. Under mild conditions, the cobalt PNP pincer complex substituted with phenyl groups on the phosphorus atoms appeared to be the most active. High rates were obtained at 120 °C, even though the addition of one equivalent of base increases the speed of the reaction drastically. Although some evidence was obtained supporting a dehydrogenation–hydrogenation mechanism, it was proven that this is not the major mechanism. Instead, the cobalt hydride complex formed by dehydrogenation of ethanol is capable of double-bond isomerization through alkene insertion–elimination.
- Spiegelberg, Brian,Dell'Acqua, Andrea,Xia, Tian,Spannenberg, Anke,Tin, Sergey,Hinze, Sandra,de Vries, Johannes G.
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supporting information
p. 7820 - 7825
(2019/05/22)
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- Manganese PNP-pincer catalyzed isomerization of allylic/homo-allylic alcohols to ketones-activity, selectivity, efficiency
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We report the first manganese catalyzed isomerization of allylic alcohols to produce the corresponding carbonyl compounds. The ligand plays a decisive role in the efficiency of this reaction. Very high conversions could be obtained using a solvent-free reaction system. A detailed DFT study reveals a self-dehydrogenation/hydrogenation reaction mechanism which was verified by the isolation of the α,β-unsaturated ketone as intermediate and a deuterium labeling experiment. It also provided a rationale for the observed selectivity and the higher efficiency of phenyl over isopropyl substitution.
- Xia, Tian,Spiegelberg, Brian,Wei, Zhihong,Jiao, Haijun,Tin, Sergey,Hinze, Sandra,De Vries, Johannes G.
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p. 6327 - 6334
(2019/11/20)
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- Mn/Cu catalyzed addition of arylboronic acid to nitriles: Direct synthesis of arylketones
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A direct and efficient synthesis of arylketones via arylboronic acid addition to nitriles in presence of inexpensive Mn/Cu catalytic system is reported. The use of non-precious Mn and Cu salts has been found to be highly advantageous both in terms of accessibility as well as cost effectiveness. A series of arylboronic acids as well as nitriles were used to synthesize a variety of symmetrical and unsymmetrical arylketones. Based on the literature studies, the reaction mechanism is anticipated to go through an aryl radical intermediate which reacted with the copper activated nitrile to give the desired arylketones after the hydrolysis of the imine intermediate.
- Moustafa, Dina,Sweet, Chelsea,Lim, Hyun,Calalpa, Brenda,Kaur, Parminder
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p. 3816 - 3820
(2018/09/18)
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- Palladium-Catalyzed Carbonylative Coupling of Aryl Iodides with Alkyl Bromides: Efficient Synthesis of Alkyl Aryl Ketones
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Alkyl aryl ketones are important structures with applications in many areas of chemistry. Hence, efficient procedures for their production are particularly attractive. In this communication, a general and efficient carbonylative cross-coupling of aryl iodides and unactivated alkyl bromides is presented. By using a simple palladium catalyst, a series of alkyl aryl ketones were synthesized in moderate to excellent yields from readily available alkyl and aryl halides in an In-Ex tube with formic acid as the CO source. In this study both primary and secondary alkyl bromides/iodides were suitable coupling partners. Additionally, this method can also be employed for the late-stage functionalization of complex natural products and polyfunctionalized molecules. (Figure presented.).
- Peng, Jin-Bao,Chen, Bo,Qi, Xinxin,Ying, Jun,Wu, Xiao-Feng
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supporting information
p. 4153 - 4160
(2018/09/21)
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- Dirhodium(ii)/P(t-Bu)3 catalyzed tandem reaction of α,β-unsaturated aldehydes with arylboronic acids
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Phosphine ligated dirhodium(ii) acetate is advocated as a catalyst for the synthesis of aryl alkyl ketones by the tandem reaction of α,β-unsaturated aromatic or aliphatic aldehydes with arylboronic acids. This tandem procedure included arylation followed by the isomerization reaction. This method exhibits good functional group tolerance and has a broad substrate scope. With the conjugated aldehydes, the one-step synthesis of γ,δ-unsaturated ketones was realized through this reaction. It is noteworthy that the length of the Rh-P bond is an important factor affecting catalytic reactions. The comparative analysis of the crystal structures of axially alkylphosphane and arylphosphane ligated dirhodium(ii) acetate revealed that the shorter Rh-P bond length favors the isomerization process as compared to the longer one. In addition, the dirhodium(ii) compound can be recovered after the completion of the reaction.
- Ma, Ziling,Wang, Yuanhua
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supporting information
p. 7470 - 7476
(2018/10/24)
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- Study on the design, synthesis and structure-activity relationships of new thiosemicarbazone compounds as tyrosinase inhibitors
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52 Structure-based thiosemicarbazone compounds bearing various substituted-lipophilic part, including substituted-benzaldehyde, substituted-phenylalkan-1-one and their biphenyl-type thiosemicarbazone analogs, were designed, synthesized and evaluated as new tyrosinase inhibitors. The results demonstrated that 22 compounds have potent inhibitory activities against tyrosinase with the IC50 value of lower than 1.0 μM. On the basis of the obtained experimental data, the structure-activity relationships (SARs) were rationally derived. Besides, the inhibition mechanism and the inhibitory kinetics of selected compounds 3d and 6e were investigated, revealing that such type of compounds were belonged to the reversible and competitive tyrosinase inhibitors. To verify the safety of these developed thiosemicarbazone compounds, four randomly selected compounds 3d, 4e, 6a and 9a were also tested in 293T cell line for the evaluation of the cytotoxicity. Interestingly, all these compounds almost did not perform any toxicity to 293T cells even at a high concentration of 1000 μmol/L. Taken together, these results suggested that such compounds could serve as the highly efficient and more safe candidates for the treatment of tyrosinase-related disorders.
- Song, Senchuan,You, Ao,Chen, Zhiyong,Zhu, Guoxun,Wen, Huan,Song, Huacan,Yi, Wei
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p. 815 - 825
(2017/09/05)
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- Iron-Catalyzed Radical Decarboxylative Oxyalkylation of Terminal Alkynes with Alkyl Peroxides
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An iron-catalyzed oxyalkylation of alkynes with alkyl peroxides as the alkylating reagents has been investigated. Alkyl peroxides are readily available from aliphatic acids and serve simultaneously as the alkylating reagents and internal oxidants. Primary, secondary, and tertiary alkyl groups of aliphatic acids were readily incorporated into C?C triple bonds and diverse α-alkylated ketones were synthesized. Mechanism studies revealed that this reaction involves highly reactive alkyl free radicals. A unique equilibrium between lauric acid and water catalyzed by the iron(III) catalyst was observed.
- Zhu, Xiaotao,Ye, Changqing,Li, Yajun,Bao, Hongli
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supporting information
p. 10254 - 10258
(2017/08/07)
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- KOtBu-Mediated Domino Isomerization and Functionalization of Aromatic Allylic Alcohols
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Transition-metal- as well as ligand-free base-mediated domino isomerization and alkylation of allylic alcohols is presented. This protocol features the conversion of simple allylic alcohols into the corresponding ketones through isomerization in the presence of a simple base. Significantly, these in situ generated ketones subsequently undergo alkylation with styrenes as electrophiles, in a domino one-pot fashion, as an atom- and step-economical chemical process.
- Suchand, Basuli,Satyanarayana, Gedu
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p. 3886 - 3895
(2017/07/22)
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- COMPOSITIONS CONTAINING, METHODS INVOLVING, AND USES OF NON-NATURAL AMINO ACIDS AND POLYPEPTIDES
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Disclosed herein are non-natural amino acids and polypeptides that include at least one non-natural amino acid, and methods for making such non-natural amino acids and polypeptides. The non-natural amino acids, by themselves or as a part of a polypeptide, can include a wide range of possible functionalities, but typical have at least one oxime, carbonyl, dicarbonyl, and/or hydroxylamine group. Also disclosed herein are non-natural amino acid polypeptides that are further modified post-translationally, methods for effecting such modifications, and methods for purifying such polypeptides. Typically, the modified non-natural amino acid polypeptides include at least one oximine, carbonyl, dicarbonyl, and/or hydroxylamine group. Further disclosed are methods for using such non-natural amino acid polypeptides and modified non-natural amino acid polypeptides, including therapeutic, diagnostic, and other biotechnology uses.
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- Merging Photoredox and Nickel Catalysis: The Direct Synthesis of Ketones by the Decarboxylative Arylation of α-Oxo Acids
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The direct decarboxylative arylation of α-oxo acids has been achieved by synergistic visible-light-mediated photoredox and nickel catalysis. This method offers rapid entry to aryl and alkyl ketone architectures from simple α-oxo acid precursors via an acyl radical intermediate. Significant substrate scope is observed with respect to both the oxo acid and arene coupling partners. This mild decarboxylative arylation can also be utilized to efficiently access medicinal agents, as demonstrated by the rapid synthesis of fenofibrate. The direct decarboxylative arylation of α-oxo acids has been achieved by synergistic visible-light-mediated photoredox and nickel catalysis. This method offers rapid entry to aryl and alkyl ketone architectures from simple α-oxo acid precursors via an acyl radical intermediate. Significant substrate scope is observed with respect to both the oxo acid and arene coupling partners.
- Chu, Lingling,Lipshultz, Jeffrey M.,Macmillan, David W. C.
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supporting information
p. 7929 - 7933
(2015/06/30)
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- Silylated organometals: A family of recyclable homogeneous catalysts
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A general strategy has been developed to synthesize a family of silylated organometals (M-PPh2-TS and DPEN-Ru-PPh2-Ts, M = Pd2+, Rh+, Pt2+, Ir+, or Ru2+, PPh2-Ts = PPh2CH2CH2Si(OEt)3), DPEN = (1R,2R)-1,2-diphenylethylenediamine). They can act as homogeneous catalysts with high efficiencies in various organic reactions using THF, CH2Cl2 or toluene as the reaction medium. After reaction, they could be thoroughly settled down by adding pentane and then used repeatedly owing to the complete catalyst recovery and good preservation of the catalyst structure. This is particularly important due to the increasing concerns regarding the cost, toxicity and limited availability of these nonrenewable transition metals.
- Huang, Jian-Lin,Wang, Jun-Zhong,Li, He-Xing,Guo, Haibing,O'Doherty, George A.
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p. 1473 - 1478
(2015/03/18)
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- DECARBOXYLATIVE CROSS-COUPLING AND APPLICATIONS THEREOF
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Methods described herein enable the production of numerous molecular species through decarboxylative cross-coupling via use of photoredox and transition metal catalysts. For example, methods described herein enable the production of numerous molecular species through decarboxylative cross-coupling via use of photoredox and transition metal catalysts. A method described herein, in some embodiments, comprises providing a reaction mixture including a photoredox catalyst, a transition metal catalyst, a coupling partner and a substrate having a carboxyl group. The reaction mixture is irradiated with a radiation source resulting in cross-coupling of the substrate and coupling partner via a mechanism including decarboxylation, wherein the coupling partner is selected from the group consisting of a substituted aromatic compound and a substituted aliphatic compound.
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Page/Page column 31; 32; 35
(2015/12/09)
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- Palladium(II)-catalyzed desulfitative synthesis of aryl ketones from sodium arylsulfinates and nitriles: Scope, limitations, and mechanistic studies
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A fast and efficient protocol for the palladium(II)-catalyzed production of aryl ketones from sodium arylsulfinates and various organic nitriles under controlled microwave irradiation has been developed. The wide scope of the reaction has been demonstrated by combining 14 sodium arylsulfinates and 21 nitriles to give 55 examples of aryl ketones. One additional example illustrated that, through the choice of the nitrile reactant, benzofurans are also accessible. The reaction mechanism was investigated by electrospray ionization mass spectrometry and DFT calculations. The desulfitative synthesis of aryl ketones from nitriles was also compared to the corresponding transformation starting from benzoic acids. Comparison of the energy profiles indicates that the free energy requirement for decarboxylation of 2,6-dimethoxybenzoic acid and especially benzoic acid is higher than the corresponding desulfitative process for generating the key aryl palladium intermediate. The palladium(II) intermediates detected by ESI-MS and the DFT calculations provide a detailed understanding of the catalytic cycle. (Figure Presented).
- Skillinghaug, Bobo,Sk?ld, Christian,Rydfjord, Jonas,Svensson, Fredrik,Behrends, Malte,S?vmarker, Jonas,Sj?berg, Per J. R.,Larhed, Mats
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p. 12018 - 12032
(2015/01/16)
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- Acceptorless and base-free dehydrogenation of alcohols and amines using ruthenium-hydride complexes
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An efficient, operatively simple, acceptorless, and base-free dehydrogenation of secondary alcohols and nitrogen-containing heterocyclic compounds was achieved by using readily available ruthenium hydride complexes as precatalysts. The complex RuH2(CO)(PPh3)3 (1) and Shvo's complex (2) showed excellent activities for the dehydrogenation of secondary alcohols and nitrogen containing heterocycles. In addition to complexes 1 and 2, the complex RuH2(PPh3)4 (3) also showed moderate to excellent activity for the acceptorless dehydrogenation of nitrogen-containing heterocyclic compounds. Kinetic studies on the oxidation reaction of 1-phenylethanol using complex 1 were carried out in the presence and the absence of external triphenylphosphine (PPh3). External addition of PPh3 had a negative influence on the rate of the reaction, which suggested that dissociation of PPh3 occurred during the course of the reaction. Hydrogen was evolved from the oxidation reaction of 1-phenylethanol by using 1 mol% of 1 (88%) and 2 (92%), which demonstrated the possible usage of the catalytic systems in hydrogen generation. Copyright
- Muthaiah, Senthilkumar,Hong, Soon Hyeok
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p. 3045 - 3053
(2013/01/15)
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- Friedel-crafts acylation of arenes with carboxylic acids using polystyrene-supported aluminum triflate
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Cross-linked polystyrene-supported aluminum triflate (Ps-Al(OTf) 3) has been shown to be a mild, efficient, and chemoselective heterogeneous Lewis acid catalyst for the acylation of aromatic compounds. The catalyst can be easily prepared from cheap starting materials, is stable (as a bench top catalyst) and is reusable.
- Boroujeni, Kaveh Parvanak,Parvanak, Kamran
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experimental part
p. 155 - 163
(2012/01/02)
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- Palladium-catalyzed oxidative coupling of trialkylamines with aryl iodides leading to alkyl aryl ketones
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Chemical equations presented. A new, simple method for selectively synthesizing alkyl aryl ketones has been developed by palladium-catalyzed oxidative coupling of trialkylamines with aryl iodides. In the presence of PdCl2(MeCN)2, TBAB, and ZnO, a variety of aryl iodides underwent an oxidative coupling reaction with tertiary amines and water to afford the corresponding alkyl aryl ketones in moderate to excellent yields. It is noteworthy that this method is the first example of using trialkylamines as the carbonyl sources for constructing alkyl aryl ketone skeletons.
- Liu, Yan,Yao, Bo,Deng, Chen-Liang,Tang, Ri-Yuan,Zhang, Xing-Guo,Li, Jin-Heng
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supporting information; experimental part
p. 2184 - 2187
(2011/06/20)
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- Friedel-Crafts acylation of arenes with carboxylic acids using silica gel supported AlCl3
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Aromatic compounds react smoothly with carboxylic acids in the presence of silica gel supported aluminium trichloride to afford the corresponding ketones with high regioselectivity in high to excellent yields. The catalyst is stable (as a bench top catalyst) and can be easily recovered and reused without appreciable change in its efficiency. tuebitak.
- Parvanak Boroujeni, Kaveh
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experimental part
p. 621 - 630
(2010/11/04)
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- PHENAZINE AND QUINOXALINE SUBSTITUTED AMINO ACIDS AND POLYPEPTIDES
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Disclosed herein are non-natural amino acids and polypeptides that include at least one non-natural amino acid, and methods for making such non-natural amino acids and polypeptides. The non-natural amino acids, by themselves or as a part of a polypeptide, can include a phenazine or quinoxaline substituent. Also disclosed herein are non-natural amino acid polypeptides that are further modified post-translationally, methods for effecting such modifications, and methods for purifying such polypeptides.
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Page/Page column 171
(2008/12/07)
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- Atom-efficient cross-coupling reactions of triarylbismuths with acyl chlorides under Pd(0) catalysis
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The atom-efficient cross-coupling reaction of triarylbismuths with a variety of aliphatic, aromatic, and hetero-aromatic acyl chlorides was demonstrated to afford high yields of cross-coupled ketones under palladium catalysis. The corresponding cross-coupling reaction with diacid chlorides also furnished bis-coupled ketones in good yields.
- Rao, Maddali L.N.,Venkatesh, Varadhachari,Banerjee, Debasis
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p. 12917 - 12926
(2008/03/28)
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- One-step preparation of α-chlorostyrenes
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α-Chlorostyrenes were prepared via a one-step method involving Friedel-Crafts reaction of various aromatic substrates with acid chlorides in the presence of a heterogeneous Si-Fe catalyst.
- Borate, Hanumant B.,Gaikwad, Abaji G.,Maujan, Suleman R.,Sawargave, Sangmeshwer P.,Kalal, Kamalakar M.
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p. 4869 - 4872
(2008/02/05)
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- Pyrazolopyrimidines as therapeutic agents
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The present invention is directed to pyrazolopyrimidine derivatives of formula (I) wherein the substituents are defined herein, which are useful as kinase inhibitors and as such are useful for affecting angiogenesis and diseases and conditions associated with angiogenesis.
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- Friedel-crafts acetylation, propionylation, and butyrylation of toluene catalyzed by solid superacids
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The liquid-solid phase acetylation of toluene with acetic anhydride was carried out over solid superacids of sulfated metal oxides (SO4/MeOx) and supported metal oxides (Me1Ox/Me2Oy) selected from the results in the benzoylation of toluene with benzoic anhydride [K. Arata, H. Nakamura, and M. Shouji, Appl. Catal. A: General, 197, 213 (2000)]. The reaction was conducted by adding dropwise a mixture of 2 mmol of acetic anhydride and 2 mL of toluene onto 0.5 g of catalyst suspended in 13 mL of toluene with stirring at 110 °C in the first period of 30 min, followed by stirring the mixture for 2 h. The yields of 2′-, 3′-, and 4′-methylacetophenones in the distribution of 9-10% 2′-, 1-2% 3′and 89-90% 4′-isomers were 24 and 13% for the sulfated metal oxides of SO4/ZrO2 and SO4/SNO2, those by Pt and Ru promoted sulfated zirconias (Pt-, Ru-SO4/ZrO2) being 21 and 28%, respectively. The supported metal oxides of Fe2O3/ ZrO2 and WO3/ZrO2 gave yields of 18 and 15%, respectively. The propionylation and butyrylation of toluene with propionic and butyric anhydrides were performed over SO4/ZrO2, SO4/SnO2, Pt-SO4/ZrO2, and Ru-SO4/ZrO2; the yields of 7-9% o- and 91-93% p-isomers were 31, 26, 32, and 44% for propionylation and 46, 29, 44, and 55% for butyrylation, respectively. The SO4/ZrO2 catalyst gave a 100% yield of 4′-methoxyacetophenone for the acetylation of anisole with acetic anhydride.
- Nakamura, Hideo,Kashiwara, Yuki,Arata, Kazushi
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p. 1071 - 1074
(2007/10/03)
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- Pyrazolopyrimidines as therapeutic agents
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The present invention provides compounds of Formula I, including pharmaceutically acceptable salts and/or prodrugs thereof, where G, R2, and R3 are defined as described herein.
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- Ruthenium-catalyzed isomerization of homoallylic alcohols in water
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Through the catalysis of RuCl2(PPh3)3, the functional groups of homoallylic alcohols are repositioned to give allylic alcohols with controlled regioselectivity. The reaction proceeds most efficiently in an aqueous media. The selectivity in product formation is affected by the reaction temperature and the amount of the catalyst being used. A higher reaction temperature and the use of a smaller amount of the catalyst are preferable for the formation of allylic alcohols. The reaction process was postulated as a tandem olefin migration-allylic rearrangement. Under the same reaction conditions, the functional groups of allylic alcohols undergo allylic rearrangements.
- Wang, Dong,Chen, Dongli,Haberman, John X.,Li, Chao-Jun
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p. 5129 - 5142
(2007/10/03)
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- Radical ion probes. 2. Evidence for the reversible ring opening of arylcyclopropylketyl anions. Implications for mechanistic studies
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Aryl cyclopropyl ketones have frequently been utilized as diagnostic probes for single electron transfer (SET) for a variety of organic transformations. The implicit assumption in these studies is that the formation of rearranged product(s) signals the intermediacy of a ketyl anion. Through a detailed examination of the mechanism, kinetics, and products arising from the decay of several arylcyclopropylketyl anions (generated electrochemically), we have demonstrated that the assumptions made in the use of these substrates as SET probes are tenuous. Radical anions generated from compounds whose only substituents on the cyclopropane ring are either H or CH3 including phenyl cyclopropyl ketone (6), l-benzoyl-2-methylcyclopropane (7), l-benzoyl-2,2-dimethylcyclopropane (8), 1-benzoyl-l-methylcyclopropane (9), andp-tolyl cyclopropyl ketone (10) undergo slow and reversible ring opening. This preequilibrium is followed by a rate-limiting coupling of the ring-opened and ring-closed species. The direction of equilibrium overwhelmingly favors the ring-closed form. For 6*-, the equilibrium constant for ring opening is estimated to be 2 × 10-8 with a maximum rate constant for the forward reaction estimated to be 2 s-1 and a minimum rate constant for the reverse direction of 8 × 107 s-1. Via deuterium labeling coupled with 2H NMR and GC/MS analysis the major product arising from the dianion is demonstrated to arise via a novel intramolecular hydride-transfer process. The radical anion generated from p-cyclopropylacetophenone (11) shows no evidence for cyclopropane ring opening. 11*- decays with a bimolecular rate law forming a pinacol dimer. These observations are complemented by results obtained from semiempirical molecular orbital calculations at the AM1 level. Important factors in the design of radical ion probes based upon intramolecular rearrangements are identified and discussed.
- Tanko, James M.,Drumright, Ray E.
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p. 1844 - 1854
(2007/10/02)
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- Unsymmetrical Ketone Synthesis via Palladium Catalyzed Carbonylation of Organic Halides
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Aryl alkyl (or benzyl) ketones are selectively prepared by the reaction of aryl iodides and alkyl iodides (or benzyl chlorides) in the presence of a stoichiometric amount of zinc-copper couple and a catalytic amount of palladium(O) complex under an atmospheric pressure of carbon monoxide.
- Tamaru, Yoshinao,Ochiai, Hirofumi,Yamada, Yoshimi,Yoshida, Zen-ichi
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p. 3869 - 3872
(2007/10/02)
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