Efficient and Selective Oxidative Deprotection of Tetrahydropyranyl Ethers, Ethylene Acetals and Ketals with Silver and Sodium Bromates in the Presence of Aluminum Chloride
Selective, Convenient and Efficient Deprotection of Trimethylsilyl and Tetrahydropyranyl Ethers, Ethylene Acetals and Ketals with Oxone under Non-aqueous Conditions
An efficient and selective method for the deprotection of trimethylsilyl (TMS) and tetrahydropyranyl (THP) ethers, ethylene acetals and ketals to their corresponding alcohols and carbonyl compounds using oxone in refluxing acetonitrile is described. Excellent chemoselectivity of this method makes it a useful and practical procedure in organic synthesis.
OXIDATIVE DEPROTECTION OF TRIMETHYLSILYL ETHERS, TETRAHYDROPYRANYL ETHERS, AND ETHYLENE ACETALS WITH BENZYLTRIPHENYLPHOSPHONIUM PEROXYMONOSULFATE UNDER MICROWAVE IRRADIATION
作者:A. R. Hajipour、S. E. Mallakpour、I. M. Baltork、H. Adibi
DOI:10.1081/scc-100103980
日期:2001.1
This paper describes the oxidation deprotection of trimethylsilyl ethers, tetrahydrophyranyl ethers and deprotection of ethylene acetals to afford carbonyl compounds using benzyltriphenylphosphonium peroxymonosulfate (1) (PhCH2PPh3HSO5) in the presence of a catalytic amount of bismuth chloride under microwave irradiation. This reagent is a stable white powder, which has been prepared by the dropwise
AN EASY AND FAST METHOD FOR OXIDATIVE DEPROTECTION OF TRIMETHYLSILYL ETHERS, TETRAHYDROPYRANYL ETHERS, AND ETHYLENE ACETALS WITH KMnO<sub>4</sub> SUPPORTED ON ALUMINA UNDER SOLVENT-FREE CONDITIONS
作者:A. R. Hajipour、S E. Mallakpour、I. M. Baltork、H. Backnezhad
DOI:10.1081/scc-120002518
日期:2002.1.1
ABSTRACT A manipulatively simple and rapid method for oxidation deprotection of trimethylsilylethers, tetrahydropyranyl ethers and deprotection of ethylene acetals to afford carbonyl compounds undersolvent-freeconditions in the presence or absence of alumina with potassium permanganate.
Efficient and Selective Oxidative Deprotection of Tetrahydropyranyl Ethers, Ethylene Acetals and Ketals with Silver and Sodium Bromates in the Presence of Aluminum Chloride
作者:Iraj Mohammadpoor-Baltork、Ali Reza Nourozi
DOI:10.1055/s-1999-3410
日期:1999.3
Primary and secondary tetrahydropyranyl (THP) ethers are efficiently transformed to their carbonyl compounds with AgBrO3 and NaBrO3/AlCl3. Ethylene acetals and ketals are transformed to their carboxylic acids and ketones respectively with AgBrO3/AlCl3 in refluxing acetonitrile. AgBrO3/AlCl3 is also able to transform ethylene acetals to aldehydes in refluxing carbon tetrachloride in high yields. In refluxing acetonitrile, ethylene acetals and ketals are transformed to aldehydes and ketones with NaBrO3/AlCl3. We have also found that tetrahydropyranyl ethers are oxidized selectively in the presence of ethylene acetals and ketals with these reagents.
Deprotection of Trimethylsilyl and Tetrahydropyranyl Ethers and of Ethylene Acetals with Tetramethylammonium Chlorochromate
作者:Abdol R. Hajipour、Arnold E. Ruoho
DOI:10.1081/scc-120016344
日期:2003.1.4
Abstract This paper describes the preparation of tetramethylammonium chlorochromate (TMACC) as a new and efficient reagent for the oxidative deprotection of trimethylsilyl and tetrahydropyranylethers or ethylene acetals and ketals to the corresponding carbonyl compounds in refluxing acetonitrile in the presence of catalytic amounts of aluminum chloride.