- A crystalline, internally-coordinated chloroborane for asymmetric hydroboration
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Asymmetric hydroboration is an important method in the preparation of enantiomerically-enriched compounds that are necessary in many areas of chemistry. Here is reported the preparation of a unique chiral chloroborane-internal ether complex and its applic
- von Dollen, Breanna,Wood, John L.,Savage, Quentin R.,Jones, Andrew J.,Garner, Charles M.
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supporting information
(2022/02/01)
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- Enantioselective Synthesis Muqubilin and Negombatoperoxides B and C/D
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Muqubilin, negombatoperoxide B, and negombatoperoxide C/D were synthesized through enantioselective routes, with the quaternary center derived from a peroxy chiral building block of known absolute configuration. The C-2/C-3 stereogenic centers were introduced by asymmetric aldol condensation, and the 1,2-dioxane ring was constructed via an intramolecular alkylation of a hydroperoxide with a mesylate. The synthetic samples showed physical and spectroscopic data consistent with those reported in the literature and thus verified the configurations of the natural products. A potentially more expeditious enantioselective entry to the 1,2-dioxane-aldol moiety (C-1 to C-6) of such cyclic peroxides was also briefly explored, where the C-2/C-3 stereogenic centers were installed through a [2+2] cycloaddition and the 1,2-dioxane ring was closed via an intramolecular alkylation coupled with an alkyl-oxygen cleavage of a β-lactone.
- Wang, Xiao-Tao,Wu, Yikang
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p. 4205 - 4219
(2021/03/01)
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- PROCESS FOR PRODUCING HYDROXYMETHYL-ALCOHOLS
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The present invention relates to a process for producing an organic compound A, which comprises at least one primary alcoholic hydroxy group and at least one secondary alcoholic hydroxy group, comprising a process step, wherein a compound B, which comprises at least one nitrile group and at least one ketone group, is reacted with hydrogen and water in the presence of at least one homogeneous transition metal catalyst TMC 1.
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Page/Page column 27
(2020/06/19)
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- Ruthenium-Catalyzed Deaminative Hydrogenation of Amino Nitriles: Direct Access to 1,2-Amino Alcohols
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A new approach for the efficient and highly selective synthesis of 1,2-amino alcohols by direct reductive hydrolysis of N-formyl-protected α-amino nitriles is reported. The commercially available RuHCl(CO)(PPh3)3 complex was found to be a suitable catalyst for this operationally simple protocol, in which no stoichiometric amounts of undesired metal waste are generated. The deaminative hydrogenation is performed at 55 bar of H2, using a 6:1 mixture of 1,4-dioxane/water as solvent. In addition, hydroxymethyl alcohols were prepared from cyanoketones under very similar conditions.
- Calleja, Pilar,Ernst, Martin,Hashmi, A. Stephen K.,Schaub, Thomas
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supporting information
p. 9498 - 9503
(2019/04/30)
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- Metal complex and preparation method and application thereof
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The invention discloses a post-transition metal bisphosphine diamine complex catalyst which is good in substrate applicability, and capable of efficiently catalyzing a hydrogenation alcohol productionreaction of various carbonyl derivatives such as esters, amides and carbonates different in structure. Central metal coordination of the metal complex catalyst has two diaminodiphosphine ligands o-PPh2C6H4NR1R2 and Ph2PCH2CH2NR3R4 (or o-PPh2C6H4CH2NR3R4, Ph2P(CH2) 3NR3R4) different in structure, and the metal complex can be obtained through a simple two-step synthesis method. The catalysts show the advantages of the two ligands in the catalytic hydrogenation process, and the defects of a complex catalyst formed by a single ligand in the aspect of applicability of substrates can be effectivelyovercome.
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Paragraph 0034; 0049; 0054
(2019/06/07)
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- A 5 - hydroxymethyl furfural catalytic conversion of 1, 6 - hexane diol (by machine translation)
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The present invention provides a 5 - hydroxymethyl furfural catalytic conversion of 1, 6 - hexane diol. The method in order to 5 - hydroxymethyl furfural as raw material, the catalyst active component is M - ReOx load on the catalyst, 50 - 200 °C, hydrogen pressure 1 - 13 mpa after a step under the condition of the catalytic conversion process, the realization of the 5 - hydroxymethyl furfural raw material high-efficiency, high selectivity, high yield in the preparation of 1, 6 - hexanediol. The present invention provides a reaction with raw material from the biomass, the presence of a regeneration, green and the like. At the same time, this reaction the atom economy is high. In addition, with the other in order to biomass as raw materials to make the 1, 6 - hexanediol technical phase comparison, this process has reaction time is short, 1, 6 - hexanediol good selectivity, space-time yield and the like. (by machine translation)
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Paragraph 0031; 0038; 0043; 0046; 0047; 0048; 0049; 0050
(2017/07/22)
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- METHODS OF PRODUCING COMPOUNDS FROM 5-(HALOMETHYL)FURFURAL
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Provided herein are methods of producing compounds, such as cyclohexanone, hexanediamine, hexanediol, hexamethylenediamine, caprolactam and nylon, from 5-(halomethyl)furfural.
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- Synthesis of 1,6-hexanediol from HMF over double-layered catalysts of Pd/SiO2 + Ir-ReOx/SiO2 in a fixed-bed reactor
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1,6-Hexanediol (1,6-HDO) was effectively prepared from 5-hydroxymethylfurfural (HMF) over double-layered catalysts of Pd/SiO2 + Ir-ReOx/SiO2 in a fixed-bed reactor. Under optimal reaction conditions (373 K, 7.0 MPa H2, in solvent mixtures of 40% water and 60% tetrahydrofuran (THF)), 57.8% yield of 1,6-HDO was obtained. The double-layered catalysts loaded in double-layered beds showed much superior performance compared to that of a single catalyst of Pd-Ir-ReOx/SiO2, even when the same amount of active components were used in the catalysts. The reaction solvent significantly affected product distributions, giving a volcano-shape plot for the 1,6-HDO yield as a function of the ratio of water to THF. Br?nsted acidic sites were generated on the catalyst in the presence of water which played determining roles in 1,6-HDO formation. A high pressure of H2 contributed to 1,6-HDO formation by depressing the over-hydrogenolysis of reaction intermediates and products to form hexane and hexanol. The reaction route was proposed for HMF conversion to 1,6-HDO on the basis of conditional experiments.
- Xiao, Bin,Zheng, Mingyuan,Li, Xinsheng,Pang, Jifeng,Sun, Ruiyan,Wang, Hua,Pang, Xiaoli,Wang, Aiqin,Wang, Xiaodong,Zhang, Tao
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p. 2175 - 2184
(2016/04/19)
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- METHODS OF PRODUCING COMPOUNDS FROM 5-(HALOMETHYL)FURFURAL
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Provided herein are methods of producing compounds, such as cyclohexanone, hexanediamine, hexanediol, hexamethylenediamine, caprolactam and nylon, from 5- (halomethyl)furfural.
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- Formal hydration of non-activated terminal olefins using tandem catalysts
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The hydration of terminal olefins to secondary alcohols has been achieved using a Pd(ii)/Ru(ii) catalyst combination with high regioselectivity and yields. Both vinyl arenes and aliphatic olefins can be hydrated easily with the tandem catalyst system using a low catalyst loading of 1 mol%. The Royal Society of Chemistry 2014.
- Yang, Yongsheng,Guo, Jiayi,Ng, Huimin,Chen, Zhiyong,Teo, Peili
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supporting information
p. 2608 - 2611
(2014/03/21)
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- An enzymatic domain for the formation of cyclic ethers in complex polyketides
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Champion cyclist: In vitro studies on the pederin biosynthetic pathway identify pyran synthases (PS) as a new family of polyketide synthase domains that stereoselectively form diverse five- and six-membered ether rings by oxa-conjugate cyclization during carbon-chain elongation. These domains could be useful tools for chemoenzymatic synthesis.
- Poeplau, Petra,Frank, Sarah,Morinaka, Brandon I.,Piel, Joern
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supporting information
p. 13215 - 13218
(2014/01/06)
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- PRODUCTION OF TETRAHYDROFURAN-2, 5-DIMETHANOL FROM ISOSORBIDE
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Disclosed herein are processes comprising contacting isosorbide with hydrogen in the presence of a first hydrogenation catalyst to form a first product mixture comprising tetrahydrofuran-2, 5-dimethanol. The processes can further comprise heating the first product mixture in the presence of hydrogen and a second hydrogenation catalyst to form a second product mixture comprising 1,6-hexanediol. The first and second hydrogenation catalysts can be the same or different.
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Page/Page column 28-29
(2013/07/19)
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- PROCESS FOR PREPARING 1, 6-HEXANEDIOL
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Disclosed are processes for preparing 1, 6-hexanediol and synthetic intermediates useful in the production of 1, 6-hexanediol from renewable biosources. In one embodiment, a process comprises contacting levoglucosenone with hydrogen in the presence of a first hydrogenation catalyst at a first temperature to form product mixture (I); and heating product mixture (I) in the presence of hydrogen and a second hydrogenation catalyst at a second temperature to form product mixture (II) which comprises 1, 6-hexanediol.
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- PROCESS FOR THE PRODUCTION OF HEXANEDIOLS
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Disclosed are processes for preparing 1,2-cyclohexanediol, and mixtures of 1,2-cyclohexanediol and 1,6-hexanediol, by hydrogenating 1,2,6 hexanetriol.
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Page/Page column 25-27
(2013/07/19)
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- Catalyst studies on the ring opening of tetrahydrofuran-dimethanol to 1,2,6-hexanetriol
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The metal catalyzed hydrogenolysis of the biomass-derived THF-dimethanol to 1,2,6-hexanetriol using heterogeneous catalysts was investigated. Bimetallic Rh-Re catalysts (4 wt% Rh and a Re/Rh (mol. ratio of 0.5) on a silica support gave the best performance and 1,2,6-hexanetriol was obtained in 84% selectivity at 31% conversion (120 C, 80 bar, 4 h); the selectivity reaches a maximum of 92% at 80 C. The product distribution at prolonged reaction times or higher temperatures or both shows the formation of diols and mono-alcohols, indicating that the 1,2,6-hexanetriol is prone to subsequent hydrodeoxygenation reactions. Different silica supports were investigated and optimal results were obtained with an amorphous silica featuring an intermediate surface area and an average mesopore size of about 6 nm. TPR and XPS surface analysis support the presence of mixed Rh and Re particles. The redox Reδ+/ReTotal surface ratio correlates with the conversion in a volcano type dependency. Both gas phase as well as Rh200Re1OH cluster DFT calculations support an acid-metal bifunctional mechanism and explain the products distribution.
- Buntara, Teddy,Melián-Cabrera, Ignacio,Tan, Qiaohua,Fierro, José L.G.,Neurock, Matthew,De Vries, Johannes G.,Heeres, Hero J.
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p. 106 - 116
(2013/07/27)
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- C-O bond hydrogenolysis of cyclic ethers with OH groups over rhenium-modified supported iridium catalysts
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Hydrogenolysis of tetrahydrofurfuryl alcohol to 1,5-pentanediol and other related substrates such as 3-hydroxytetrahydrofuran and 1,2-cyclohexanediol proceeds over Ir-ReOx/SiO2 catalyst. TOF values are higher than those of Rh-ReOx/SiO2, which has been reported to be an effective catalyst. The selectivity to the product, where the C-O bond neighboring the C-OH group in the substrate is dissociated, is comparable to or higher than that of Rh-ReOx/SiO2. Hydrogenolysis of most substrates except 1,2-cyclohexanediol proceeds via the direct mechanism where hydride species formed from hydrogen molecule attacks the anti-position of C-O bond. In the case of hydrogenolysis of 1,2-cyclohexanediol where attack of anti-position of C-O bond is unfavorable, indirect mechanism involving dehydrogenation to 2-hydroxycyclohexanone is responsible for the formation of cyclohexanol.
- Chen, Kaiyou,Mori, Kazuma,Nakagawa, Yoshinao,Tomishige, Keiichi,Watanabe, Hideo
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p. 171 - 183,13
(2020/07/31)
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- Catalytic hydrogenation of carboxamides and esters by well-defined Cp*Ru complexes bearing a protic amine ligand
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A novel catalytic method for the straightforward hydrogenation of carboxamides and esters to primary alcohols has been developed. Chiral modification in the ligand sphere of the well-defined Cp*Ru catalyst molecule opens up a new possibility for the development of an enantioselective hydrogenation of racemic substrates via dynamic kinetic resolution.
- Ito, Masato,Ootsuka, Takashi,Watari, Ryo,Shiibashi, Akira,Himizu, Akio,Ikariya, Takao
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supporting information; experimental part
p. 4240 - 4242
(2011/06/21)
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- Caprolactam from renewable resources: Catalytic conversion of 5-hydroxymethylfurfural into caprolactone
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Renewable nylon: 5-Hydroxymethylfurfural (HMF), which can be obtained from renewable resources such as D-fructose, was converted into caprolactone with very good overall selectivity in only three steps. The new route involves two hydrogenation steps to obtain 1,6-hexanediol, which was oxidatively cyclized to caprolactone, and then converted into caprolactam. Copyright
- Buntara, Teddy,Noel, Sebastien,Phua, Pim Huat,Melian-Cabrera, Ignacio,De Vries, Johannes G.,Heeres, Hero J.
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scheme or table
p. 7083 - 7087
(2011/09/30)
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- Selective hydrogenolysis of polyols and cyclic ethers over bifunctional surface sites on rhodium-rhenium catalysts
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A ReOx-promoted Rh/C catalyst is shown to be selective in the hydrogenolysis of secondary C-O bonds for a broad range of cyclic ethers and polyols, these being important classes of compounds in biomass-derived feedstocks. Experimentally observed reactivity trends, NH3 temperature-programmed desorption (TPD) profiles, and results from theoretical calculations based on density functional theory (DFT) are consistent with the hypothesis of a bifunctional catalyst that facilitates selective hydrogenolysis of C-O bonds by acid-catalyzed ring-opening and dehydration reactions coupled with metal-catalyzed hydrogenation. The presence of surface acid sites on 4 wt % Rh-ReOx/C (1:0.5) was confirmed by NH3 TPD, and the estimated acid site density and standard enthalpy of NH3 adsorption were 40 μmol g-1 and -100 kJ mol-1, respectively. Results from DFT calculations suggest that hydroxyl groups on rhenium atoms associated with rhodium are acidic, due to the strong binding of oxygen atoms by rhenium, and these groups are likely responsible for proton donation leading to the formation of carbenium ion transition states. Accordingly, the observed reactivity trends are consistent with the stabilization of resulting carbenium ion structures that form upon ring-opening or dehydration. The presence of hydroxyl groups that reside α to carbon in the C-O bond undergoing scission can form oxocarbenium ion intermediates that significantly stabilize the resulting transition states. The mechanistic insights from this work may be extended to provide a general description of a new class of bifunctional heterogeneous catalysts, based on the combination of a highly reducible metal with an oxophilic metal, for the selective C-O hydrogenolysis of biomass-derived feedstocks.
- Chia, Mei,Pagan-Torres, Yomaira J.,Hibbitts, David,Tan, Qiaohua,Pham, Hien N.,Datye, Abhaya K.,Neurock, Matthew,Davis, Robert J.,Dumesic, James A.
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scheme or table
p. 12675 - 12689
(2011/10/13)
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- Mechanism of the hydrogenolysis of ethers over silica-supported rhodium catalyst modified with rhenium oxide
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The Rh-ReOx/SiO2 (Re/Rh = 0.5) exhibited high activity in the hydrogenolysis of ethers with an OH group. The CO bond neighboring CH2OH group was selectively dissociated: The hydrogenolysis of tetrahydro-5-methyl-2-furfuryl alcohol and 2-isopropoxyethannol gave 1,5-hexanediol and ethanol + isopropanol, respectively. This tendency suggests the regioselective CO dissociation mechanism via anion intermediate formed by the attack of hydride and the subsequent protonation of the anion.
- Koso, Shuichi,Nakagawa, Yoshinao,Tomishige, Keiichi
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scheme or table
p. 221 - 229
(2011/07/06)
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- Organocatalytic synthesis of an alkyltetrahydropyran
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The first synthesis of an alkyltetrahydropyran using a diarylprolinol organocatalyst is described. Georg Thieme Verlag Stuttgart.
- Díez,Nú?ez,Benéitez,Moro,Marcos,Basabe,Broughton,Urones
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scheme or table
p. 390 - 394
(2009/08/07)
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- Oxygen-directed intramolecular hydroboration
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Metal-free homoallylic oxygen-directed intramolecular hydroboration is reported. Regioselectivities from 20:1 to 82:1 favoring the 1,3-dioxy-substituted products have been achieved using Me2S·BH3/TfOH followed by standard oxidative workup. Branching at the C5 position improves regioselectivity. Copyright
- Rarig, Robert-Andre F.,Scheideman, Matthew,Vedejs, Edwin
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body text
p. 9182 - 9183
(2009/02/03)
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- DERMATOLOGICAL COMPOSITIONS AND METHODS
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Disclosed are methods and compositions for regulating the melanin content of mammalian melanocytes; regulating pigmentation in mammalian skin, hair, wool or fur; treating or preventing various skin and proliferative disorders; by administration of various compounds, including alcohols, diols and/or triols and their analogues.
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- A mild and selective cleavage of tert-butyldimethylsilyl ethers by indium(III) chloride
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Alkyl tert-butyldimethylsilyl ethers are selectively deprotected to the corresponding alcohols in high yields for the first time by indium(III) chloride in refiuxing aqueous acetonitrile. Several functional groups like OBn, Boc, CBz, OBz, O-allyl, OTBDPS, OAc, OMe, ethers, esters and olefins present in the substrate are unaffected.
- Yadav,Subba Reddy,Madan
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p. 853 - 854
(2007/10/03)
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- Treatment of neurodegenerative diseases
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Disclosed are methods for increasing the differentiation of mammalian neuronal cells for purposes of treating neurodegenerative diseases or nerve damage by administration of various compounds including alcohols, diols and/or triols and their analogues.
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- Synthesis of the left hand unit of batzelladine F; revision of the reported relative stereochemistry
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The addition of guanidine to the bis-α,β-unsaturated ketone 17 is reported, leading to the formation of the tricyclic guanidine 18, the left hand portion of the naturally occurring alkaloid batzelladine F. Nmr evidence is given which casts doubt upon the assignment of the relative stereochemistry of this metabolite.
- Black, Gregory P.,Murphy, Patrick J.,Thornhill, Andrew J.,Walshe, Nigel D. A.,Zanetti, Cinzia
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p. 6547 - 6554
(2007/10/03)
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- Treatment of diseases mediated by the nitric oxide/cGMP/protein kinase G pathway
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Disclosed are methods and compositions for stimulating cellular nitric oxide (NO) synthesis, cyclic guanosine monophosphate levels (cGMP), and protein kinase G (PKG) activity for purposes of treating diseases mediated by deficiencies in the NO/cGMP/PKG signal transduction pathway, by administration of various compounds including alcohols, diols and/or triols and their analogues.
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- Selective hydroboration of alkenes and alkynes in the presence of aldehydes and ketones
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The reactions of terminal alkenes in the presence of ketones or aldehydes with a variety of borane reagents have been investigated. It was found that the selective hydroboration of a terminal alkene in the presence of a ketone or an aldehyde is most efficient when dicyclohexylborane is used as the hydroborating agent. The hydroboration of olefinic ketones and olefinic aldehydes with dicyclohexylborane generates the corresponding hydroxyaldehydes and hydroxyketones in good yields after oxidation with sodium perborate. The hydroboration of alkynyl ketones and alkynyl aldehydes with dicyclohexylborane yields the corresponding olefinic carbonyl compounds after protonation, or dicarbonyl compounds after oxidation.
- Kabalka, George W.,Yu, Su,Li, Nan-Sheng
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p. 800 - 805
(2007/10/03)
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- Cleavage of tert-butyldimethylsilyl ethers by chloride ion
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A general method for the selective cleavage of tert-butyldimethylsilyl ethers in the presence of tert-butyldiphenylsilyl ones has been established using a combination of H2O and a concentrated solution of LiCl in DMF at 90°C. Since no acids, bases, reducing or oxidizing agents are used, the method seems to be very appropiate for the deprotection of TBDMS ethers in the presence of other sensitive functional groups.
- Farras, Jaume,Serra, Carme,Vilarrasa, Jaume
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p. 327 - 330
(2007/10/03)
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- Selective hydroboration of terminal alkenes in the presence of aldehydes and ketones
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The hydroboration of olefinic ketones and aldehydes with dicyclohexylborane gives the corresponding hydroxy aldehydes and ketones in good yields after oxidation with sodium perborate.
- Kabalka, George W.,Yu, Su,Li, Nan-Sheng
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p. 5455 - 5458
(2007/10/03)
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- Selective deprotection of tert-butyldimethylsilyl ether with lithium bromide and 18-crown-6
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Lithium bromide, in the presence of a crown ether, has been found to selectively remove primary tert-butyldimethylsilyl ethers under controlled conditions. This selectivity has been utilized to synthesize 3'-TBDMS-2'- deoxyuridine in one step from the diprotected compound.
- Tandon, Manish,Begley, Tadhg P.
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p. 2953 - 2959
(2007/10/03)
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- Intramolecular H-Transfer Reactions During the Decomposition of Alkylhydroperoxides in Hydrocarbons as the Solvents
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Eight defined primary and secondary alkylhydroperoxides were decomposed in n-alkanes as the solvent, mostly in the presence of manganese stearate.In all cases the corresponding alcohols and carbonyl compounds were formed as the main products with yields of 60-90percent.Besides, difunctional products were formed by an intramolecular H-transfer in the alkoxy radicals corresponding to the starting hydroperoxides.Products possibly formed by an intramolecular H-transfer in the corresponding alkylperoxy radical could be found only in the case of 4-methyl-2-hydroperoxy pentane.The amount of products formed by intramolecular H-transfer depended on the nature of the C-H bond in δ-position to the original hydroperoxy group and lay between 4percent (primary C-H in the case of 4-hydroperoxy heptane) and 13percent (tertiary C-H in the case of 2-hydroperoxy-5-methyl hexane) with respect to the starting hydroperoxide.The amount of products formed by oxidative attack of the alkoxy and alkylperoxy radicals at the normal paraffins used as the solvents was unexpectedly low (always less than 10percent with respect to the starting hydroperoxide).An increment system is proposed for the calculation of 13C-nmr shifts in alkyl hydroperoxides.
- Jinsheng, Li,Pritzkow, Wilhelm,Voerckel, Volkmar
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- Studies on the Autoxidation of Nonbranched Aliphatic Monocarboxylic Acids and Their Methyl Esters
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Valeric, caproic, and heptanoic acid and their methyl esters were oxidizied at 140 deg C by molecular oxygen.The oxidation mixtures were reduced by LiAlH4, and the mono- and dihydroxy compounds formed were analyzed gaschromatographically.From the results obtained one can conclude that nonbranched aliphatic acids and their methyl esters are attacked by the chain-carrying peroxy radicals at the different C-H bonds with almost the same regioselectivity as normal paraffins.Only the β- and to a smaller extent the α-positions are desactivated by the neighbouring carboxylic group.
- Pritzkow, Wilhelm,Voerckel, Volkmar
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p. 572 - 578
(2007/10/02)
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- Solvomercuration-Demercuration. 8. Oxymercuration-Demercuration of Methoxy-, Hydroxy-, and Acetoxy-Substituted Alkenes
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The oxymercuration-demercuration (OM-DM) of a series of methoxy-, hydroxy-, and acetoxy-substituted alkenes was examined.The systems examined were the allyl, crotyl, 3-buten-1-yl, 4-penten-1-yl, and 5-hexen-1-yl.The methoxyalkenes undergo hydration with very high regioselectivity and almost quantitative yield in all cases.However, a small -I effect is observed in the case of the allylalkene (97.1percent Markovnikov vs. 99.5percent in 1-hexene).Moreover, in the crotyl case, a major directing effect is observed: 97.7percent 3-ol, 2.3percent 2-ol.The other three alkenes undergo the OM reaction with no effect from the methoxy group (99.5percent Markovnikov isomer).In contrast, only allyl-, crotyl-, and 3-buten-1-yl alcohols produce major amounts of hydrated products, the diols.While no hydroxyl group directing effect is observed in the allyl system, a major one is again seen in the case of the crotyl: 93.5percent l,3-diol and 6.5percent l,2-diol.The major products from the 4-penten-1-yl and 5-hexen-1-yl and alcohols are 2-methyltetrahydrofuran and 2-methyltetrahydropyran, respectively, resulting from OH-5 and OH-6 neighboring group participation in the OM stage.The acetoxy alkenes undergo hydration to give diols in ca. 80percent yield with ca. 20percent unreacted starting material.This is the result of a competitive deoxymercuration reaction which is occurring in the DM stage.However, the yield of hydrated products can be increased by varying the amount of base used in the DM.Neighboring-group participation, AcO-5, is observed in the allyl system only, resulting in a 65percent yield of the Markovnikov oxymercurial, by 1H NMR analysis, and a 35percent yield of the acetoxy-exchanged mercurial.Again, a major -I-directing effect of the acetoxy group was observed in the crotyl system but not in the others.In addition to the expected l,2- and l,3-diols, the OM-DM of crotyl acetate also resulted in small amounts of the unexpected 2,3-diol under kinetic conditions.Finally, a modified DM procedure has been developed which is compatible with the acetoxy group.
- Brown, Herbert C.,Lynch, Gary J.
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p. 531 - 538
(2007/10/02)
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