Several methyl esters were obtained by an efficient and simple one-pot procedure from the corresponding aldehydes in high yields. This procedure involves dimethyl acetal formation from aldehydes and subsequent oxidation. (C) 1998 Elsevier Science Ltd. All rights reserved.
An Efficient Method for One-Pot Reductive Cleavage of Acetals to Primary Alcohols Using a Bimetal Redox Couple CoCl2.6H2O-Zn
作者:Kuladip Sarma、Amrit Goswami
DOI:10.2174/157017809789869456
日期:2009.10.1
Acyclic or cyclic O,O-acetals and O,S-acetals underwent reductivecleavage to give primary alcohols efficiently on treatment with Zn-CoCl2.6H2O-bimetal redox system in dry tetrahydrofuran at ambient temperature to give good to excellent yields.
Reduction of aldehydes with 2-propanol proceeded efficiently by catalysis with hydrous zirconium oxide to give the corresponding alcohols. Most ketones also were reduced efficiently, but conjugated or sterically hindered ketones resisted the reduction. The reduction was carried out with primary, secondary, or tertiary alcohols, and only secondary alcohols served as hydrogen donors. Kinetic experiments
A New Method for the Preparation of δ-Alkoxy-α,β-unsaturated Aldehydes and Polyenals
作者:Akihiko Ishida、Teruaki Mukaiyama
DOI:10.1246/bcsj.50.1161
日期:1977.5
TiCl4 and also in the coexistence of TiCl4 and Ti(OiPr)4 to give δ-alkoxy-α,β-unsaturated aldehydes (3–5) in good yields. In the presence of 1,8-diazabicyclo[5.4.0] undec-7-ene or 1,5-diazabicyclo[4.3.0]non-5-ene and molecular sieves 3A or 4A, the elimination reaction of δ-alkoxyl group of α,β-unsaturated aldehydes (3–5) proceeds smoothly to afford the corresponding polyenals in good yields.
Novel Preparation of α,β-Unsaturated Aldehydes. Benzeneselenolate Promotes Elimination of HBr from α-Bromoacetals
作者:Andrei Vasil'ev、Lars Engman
DOI:10.1021/jo9917644
日期:2000.4.1
elimination/hydrolysis of these mixtures afforded alpha,beta-unsaturated aldehydes in 50-80% overall yields. In the case of tertiary alpha-bromoacetals, treatment with benzeneselenolate afforded only dehydrobromination products as mixtures of isomers. The presence of at least a catalytic amount of the organoselenium reagent was found to be crucial for olefin formation. A SET-mechanism, involving benzeneselenolate-induced