Efficient and Selective Oxidative Deprotection of Tetrahydropyranyl Ethers, Ethylene Acetals and Ketals with Silver and Sodium Bromates in the Presence of Aluminum Chloride
2,6-Dicarboxypyridinium Chlorochromate. An Efficient and Selective Reagent for the Mild Deprotection of Acetals, Thioacetals, and 1,1-Diacetates to Carbonyl Compounds
chlorochromate (2,6- DCPCC ) was found to be an efficientreagent for the conversion of acetals, thioacetals, and 1,1-diacetates to their corresponding carbonyl compounds under neutral and anhydrous conditions in good to excellent yields. Selectivedeprotection of acetals or 1,1-diacetates in the presence of thioacetals at room temperature is also observed with this reagent.
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.
AN EFFICIENT METHOD FOR SELECTIVE DEPROTECTION OF TRIMETHYLSILYL ETHERS, TETRAHYDROPYRANYL ETHERS, ETHYLENE ACETALS, AND KETALS UNDER MICROWAVE IRRADIATION
作者:A. R. Hajipour、S. E. Mallakpour、I. Mohammadpoor-Baltork、S. Khoee
DOI:10.1081/scc-120002408
日期:2002.1.1
[2.2.2]octane dichromate (BAABOD) is a useful reagent for the selective cleavage of trimethylsilyl ethers, tetrahydropyranyl ethers, ethylene acetals and ketals to their corresponding alcohols, aldehydes and ketones. This method is very simple and efficient and the reaction has been carried out under microwave irradiation.
Intermolecular Reactions of Chlorohydrine Anions: Acetalization of Carbonyl Compounds under Basic Conditions
作者:Michał Barbasiewicz、Mieczysław Ma̧kosza
DOI:10.1021/ol0613113
日期:2006.8.1
[reaction: see text] Nonenolizable aldehydes and ketones react with 2-chloroethanol and 3-chloropropanol under basic conditions (t-BuOK, DMF/THF) with formation of 2-substituted 1,3-dioxolanes and 1,3-dioxanes, respectively. Conversion of the two-step addition-alkylation process depends on the electrophilicity of the carbonyl group that governs the equilibrium of addition of chloroalkoxides. This method
Various types of aromatic aldehydes were efficiently converted to their corresponding 1,3-dioxanes and 1,3-dioxolane with 1,3-propanediol and ethylene glycol, respectively, in the presence of catalytic amount of ZrO(OTf)2 in acetonitrile at room temperature. The catalyst can be reused several times without loss of its catalytic activity. Very short reaction times, selective acetalization of aromatic