82073-55-0Relevant articles and documents
Protection and deprotection of acetals by using MoO3/SiO 2
Bhosale, Rajesh S.,Bhosale, Sidhanath V.,Bhosale, Sheshanath V.,Solanke, Kuldeep S.,Pawar, Rajendra P.,Chougule, Harish S.,Dongare, Mohan K.
, p. 659 - 663 (2006)
Acetalization of aldehydes using a new silica-supported molybdenum(VI) oxide (20%) catalyst has been explored. Additionally, facile deprotection strategy for the acetals is reported including the results from the replacement of solvent studies. The protocol achieved the protection O,O-acetals in excellent yield within a few hours under neutral conditions and also deprotection of aromatic O,O-acetals in excellent yields was achieved within a few minutes in aqueous acetone. Copyright Taylor & Francis Group, LLC.
Selective Catalytic Transesterification, Transthiolesterification, and Protection of Carbonyl Compounds over Natural Kaolinitic Clay
Ponde, Datta E.,Deshpande, Vishnu H.,Bulbule, Vivek J.,Sudalai, Ammugam,Gajare, Anil S.
, p. 1058 - 1063 (2007/10/03)
Transesterification and transthiolesterification of β-keto esters with variety of alcohols and thiols and selective protection of carbonyl functions with various protecting groups catalyzed by natural kaolinitic clay are described. The clay has been found to be an efficient catalyst in transesterifying long chain alcohols, unsaturated alcohols, and phenols to give their corresponding β-keto esters in high yields. For the first time, transthiolesterification of β-keto esters with a variety of thiols has been achieved under catalytic conditions. Clay also catalyzes selective transesterification of β-keto esters by primary alcohols in the presence of secondary and tertiary alcohols giving corresponding β-keto esters. A systematic study involving the reactivity of different nucleophiles (alcohols, amines, and thiols) toward β-keto esters is also described. Sterically hindered carbonyl groups as well as α,β-unsaturated carbonyl groups underwent protection without the deconjugation of the double bond. Chemoselective protection of aldehydes in the presence of ketones has also been achieved over natural kaolinitic clay.
Natural kaolinitic clay: A remarkable reusable solid catalyst for the selective functional protection of aldehydes and ketones
Ponde, Datta,Borate,Sudalai,Ravindranathan,Deshpande
, p. 4605 - 4608 (2007/10/03)
Natural kaolinitic clay possessing transition metals such as Fe and Ti in its lattice has been found to catalyze efficiently the chemoselective acetalization and thioacetalization of variety of carbonyl compounds with ethane - 1,2 - diol and ethane - 1,2 - dithiol respectively.
