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
Radical-Hydroboration-Involved One-Pot Synthesis of Boron-Handled Glycol Derivatives
作者:Feng-Lian Zhang、Yi-Feng Wang、Bi-Yang Zhuang、Ji-Kang Jin
DOI:10.1055/s-0040-1707142
日期:2021.3
A one-pot two-step protocol for the direct synthesis of boron-handled glycol derivatives is reported. The procedure starts by an NHC–boryl-radical-promoted regioselective hydroboration of glycol-protected cinnamaldehydes. After that, the reaction mixture is treated with pinacol in the presence of HCl, leading to the direct formation of pinacol boronate handled glycol monoalkyl ethers. In this acid-triggered
Poly(N-bromobenzene-1,3-disulfonamide) and N,N,N′,N′-tetrabromobenzene-1,3-disulfonamide as a mild and efficient catalyst for chemoselective thioacetalization of carbonyl functions and transthioacetalization reactions
Poly(N‐bromobenzene‐1,3‐disulfonamide) and N,N,N′,N′‐tetrabromobenzene‐1,3‐disulfonamide are effective catalysts for chemoselective dithioacetalization of aldehydes in the presence of ketones under neutral conditions. J. Heterocyclic Chem., (2011).
Photoreactions of various dithioacetals and ketals using tris(p-chlorophenyl)pyrylium perchlorate as a sensitizer were studied. Irradiation (λ&>360 nm) of dichloromethane solutions containing dithioacetals or ketals and pyryliumsalt afforded the corresponding carbonyl compounds in good to excellent yields in the presence of molecular oxygen.