Transdithioacetalization of acetals, ketals, oximes, enamines and tosylhydrazones catalysed by natural kaolinitic clay
作者:G. K. Jnaneshwara、N. B. Barhate、A. Sudalai、V. H. Deshpande、R. D. Wakharkar、A. S. Gajare、M. S. Shingare、R. Sukumar
DOI:10.1039/a706475f
日期:——
Natural kaolinitic clay efficiently catalyses the transdithioacetalization of acetals, ketals, oximes, enamines and tosylhydrazones with ethane-1,2-dithiol and propane-1,3-dithiol to produce the corresponding dithiolanes in high yields.
Natural kaolinitic clay possessing transition metals such as Fe and Ti in its lattice has been found to catalyze efficiently the chemoselectiveacetalization and thioacetalization of variety of carbonyl compounds with ethane-1,2-diol and ethane-1,2-dithiolrespectively.
Copper(II) tetrafluoroborate as an extremely efficient catalyst for 1,3-dithiolane/dithiane formation from carbonyl compounds under solvent-free conditions at room temperature
作者:Ram C. Besra、Santosh Rudrawar、Asit K. Chakraborti
DOI:10.1016/j.tetlet.2005.07.059
日期:2005.9
formation from aromatic, heteroaromatic and aliphatic aldehydes and cyclic saturated ketones in 1–5 min under solvent-free conditions at room temperature. The reaction is compatible with other functionalities such as ether, ester, hydroxyl, halide, nitro and cyano groups and exhibits excellent chemoselectivity. α,β-Unsaturated aldehydes/ketones lead to selective formation of 1,3-dithiolanes instead of
Selective Transdithioacetalization of Acetals, Ketals, Oxathioacetals and Oxathioketals Catalyzed by Envirocat EPZ10R
作者:A. S. Gajare、M. S. Shingare、B. P. Bandgar
DOI:10.1039/a800864g
日期:——
Envirocat EPZ10R has been found to be a remarkable reusable heterogeneous catalyst for selective transdithioacetalization of acetals, ketals, oxathioacetals and oxathioketals with HSCH2CH2SH and HSCH2CH2CH2SH.