2,4,4,6-Tetrabromo-2,5-cyclohexadienone (TABCO), N-Bromosuccinimide (NBS) and Bromine as Efficient Catalysts for Dithioacetalization and Oxathioacetalization of Carbonyl Compounds and Transdithioacetalization Reactions
作者:Nasser Iranpoor、Habib Firouzabadi、Hamid Reza Shaterian、M. A. Zolfigol
DOI:10.1080/10426500211712
日期:2002.5.1
6-tetrabromo-2,5-cyclohexadienone (TABCO), N-bromosuccinimide (NBS), and bromine as efficient catalysts for conversion of carbonyl compounds to their cyclic and acyclic dithioacetals and 1,3-oxathiolanes under mild reaction conditions are described. These catalysts are also used for efficient transdithioacetalization of acetals, diacetals, ketals, acylals, enamines, hydrazones, and oximes with high
A new method for the generation of benzyl radicalsfrom acetals via low-valent titanium-mediated homolytic C–O bond cleavage is presented. The low cost and availability of the developed titanium reagent enable efficient access to α-alkoxy carbon radicalspecies via the developed reaction.
Sulfamic Acid as a Cost‐Effective and Recyclable Catalyst for Protection of Carbonyls to Acetals and Ketals Under Mild Conditions
作者:Weizhong Gong、Bo Wang、Yanglong Gu、Liang Yan、Liming Yang、Jishuan Suo
DOI:10.1081/scc-200039314
日期:2004.12.31
Abstract An efficient H2NSO3H‐catalyzed protection of various carbonyl compounds at room temperature was investigated. The features of mild conditions, cost‐efficient catalyst, simple workup, and the recyclability of the catalyst were represented in this process.
2,3-Dichloro-5,6-dicyano-<i>p</i>-benzoquinone (DDQ) as a Highly Efficient and Mild Catalyst for Diethyl Acetalization of Carbonyl Compounds
作者:Babak Karimi、Ashraf Miri Ashtiani
DOI:10.1246/cl.1999.1199
日期:1999.11
Various types of structurally different carbonyl compounds in the presence of ethyl orthoformate (EtO)3CH could be efficiently converted to their diethyl acetals by using a catalytic amount (1-3 mol%) of DDQ under mild reaction conditions.
Zirconium Tetrachloride (ZrCl<sub>4</sub>) Catalyzed Highly Chemoselective and Efficient Acetalization of Carbonyl Compounds
作者:Habib Firouzabadi、Nasser Iranpoor、Babak Karimi
DOI:10.1055/s-1999-2605
日期:1999.3
Zirconium tetrachloride (ZrCl4) is a highly efficient and chemoselective catalyst for the acetalization, and in-situ transacetalization of carbonyl compounds under mild reaction conditions.