Dicyanoketene Ethylene Acetal as a Mild and Efficient Catalyst for Tetrahydropyranylation of Alcohols
作者:Tsuyoshi Miura、Yukio Masaki
DOI:10.1080/00397919508015875
日期:1995.7
Abstract Alcohols can react with 3,4-dihydro-2H-pyran in the presence of a catalytic amount of dicyanoketene ethylene acetal under neutral conditions to afford the corresponding tetrahydropyranyl ethers in good yields.
Chloral Hydrate as a Water Carrier for the Efficient Deprotection of Acetals, Dithioacetals, and Tetrahydropyranyl Ethers in Organic Solvents
作者:Sosale Chandrasekhar、Annadka Shrinidhi
DOI:10.1080/00397911.2013.876652
日期:2014.7.3
Abstract The efficientdeprotection of several acetals, dithioacetals, and tetrahydropyranyl (THP) ethers under ambient conditions, using chloral hydrate in hexane, is described. Excellent yields were realized for a wide range of both aliphatic and aromatic substrates. The method is characterized by mild conditions (room temperatures or below), simple workup, and the ready availability of chloral hydrate
4-Aminophenyldiphenylphosphinite (APDPP), a new heterogeneous and acid scavenger phosphinite — Conversion of alcohols, trimethylsilyl, and tetrahydropyranyl ethers to alkyl halides with halogens or <i>N</i>-halosuccinimides
conversion of alcohols, trimethylsilyl ethers, and tetrahydropyranyl ethers to their corresponding bromides, iodides, and chlorides in the presence of molecular halogens or N-halosuccinimides. The amino group in this phosphinite acts as an acid scavenger and removes the produced acid. A simple filtration easily removes the phosphinate by-product.Key words: 4-aminophenyldiphenylphosphinite, alcohol, trimethylsilyl
Silica‐Gel‐Supported Aluminium Chloride: A Stable, Efficient, Selective, and Reusable Catalyst for Tetrahydropyranylation of Alcohols and Phenols
作者:Kaveh Parvanak Borujeni
DOI:10.1080/00397910600764725
日期:2006.9
Abstract A simple, effective, and highly chemoselective method to form 2‐tetrahydropyranyl ethers of alcohols and phenols in the presence of silica‐gel‐supported aluminium chloride as a heterogeneous Lewisacidcatalyst is described. The catalyst can be easily recovered and reused without appreciable change in its efficiency.
Utility of 3,4-Dimethoxybenzyl (DMPM) Glycosides. A New Glycosylation Triggered by 2,3-Dichloro-5,6-dicyano-<i>p</i>-benzoquinone (DDQ) Oxidation
作者:Junji Inanaga、Yasuo Yokoyama、Takeshi Hanamoto
DOI:10.1246/cl.1993.85
日期:1993.1
A new glycosylation which proceeds through the formation of charge transfer (CT) complex of DMPM glycosides with DDQ followed by the oxidation-triggered fragmentation of the intermediates has been developed. Primary, secondary, and tertiary alcohols are used as glycosyl acceptors for the formation of 2-deoxyglycoside derivatives.