New Applications of 2,4,6-Trichloro-1,3,5-triazine (TT) in Synthesis: Highly Efficient and Chemoselective Deprotection and Ring-Enlargement of Dithioacetals and Oxathioacetals
AN EFFICIENT METHOD FOR THE THIOACETALIZATION OF CARBONYL COMPOUNDS IN THE PRESENCE OF CATALYTIC AMOUNTS OF BENZYLTRIPHENYLPHOSPHONIUM TRIBROMIDE
作者:A. R. Hajipour、S. A. Pourmousavi、A. E. Ruoho
DOI:10.1080/00304940709458596
日期:2007.8
in multi-step syntheses. Among carbonyl protecting groups, dithioacetals constitute an important class of compounds as acyl anion equivalents' or masked methylene functions in carbon-carbon bond forming reactions. They are versatile2 due to their straightforward preparation and also to their stability under basic or mildly acidicconditions. Although several methods have been reported for protection
An Efficient Method for Thioacetalization of Carbonyl Compounds in the Presence of a Catalytic Amount of Benzyltriphenylphosphonium Tribromide Under Solvent-Free Conditions
作者:Abdol R. Hajipour、Seied A. Pourmousavi、Arnold E. Ruoho
DOI:10.1080/10426500601088739
日期:2007.3.15
variety of carbonylcompounds have been successfully converted to the corresponding thioacetal derivatives in good to excellent yields on the reaction of carbonylcompounds with 1,2-ethanedithiole, 1,3-propanedithiol, and ethanethiol in the presence of catalytic amount of benzyltriphenylphosphonium tribromide under solvent-free conditions. Some of the major advantages of this method are mild reaction conditions
Enantioselective Vanadium-Catalyzed Oxidation of 1,3-Dithianes from Aldehydes and Ketones using β-Amino Alcohol Derived Schiff Base Ligands
作者:Yinuo Wu、Fei Mao、Fanchao Meng、Xingshu Li
DOI:10.1002/adsc.201000803
日期:2011.7
and ketones by β‐amino alcohol‐derived Schiffbase ligands with two stereogenic centers was investigated. Usingaqueoushydrogenperoxide as the oxidant and the Schiffbase 3b as a chiral ligand, a variety of 1,3‐dithianes derived from aldehydes were easily converted into the corresponding mono‐sulfoxides in good yields (81–88%) with excellent enantioselectivities (up to 99% ee). Additionally, 99% ee
Neutral Lithium Triflate (LiOTf) Efficiently Catalyzes Chemoselective Preparations of Cyclic and Acyclic Dithioacetals from Carbonyl Compounds, Acylals, and O,O-Cyclic and Open-Chain Acetals under Solvent-Free Conditions
作者:Habib Firouzabadi、Shahram Eslami、Babak Karimi
DOI:10.1246/bcsj.74.2401
日期:2001.12
An efficient and chemoselective preparation of cyclic and acyclic thioacetals from carbonyl compounds, cyclic and acyclic acetals and acylals in the presence of catalytic amounts of neutral lithium triflate and thiols undersolvent-freeconditions is described.
Trichloromelamine (TCM) – Catalyzed Efficient and Selective Thioacetalization of Aldehydes and Transthioacetalization of Acetals and Oxathioacetals under Mild Reaction Conditions
作者:Hassan Hazarkhani
DOI:10.1080/00397910802219338
日期:2008.7.24
Abstract Trichloromelamine was used effectively as a catalyst for thioacetalization of aldehydes and transthioacetalization of acetals and oxathioacetals undermild and almost neutral reaction conditions. By this method, aldehydes, acetals, and oxathioacetals were selectively protected in the presence of ketones as their 1,3-dithiolanes or 1,3-dithianes.