Facile synthetic methods of acetals and crown ethers from the reaction of diphenyldiazomethane with 2,3-dichloro-5,6-dicyanobenzoquinone in the presence of alcohols
作者:Takumi Oshima、Ryoji Nishioka、Toshikazu Nagai
DOI:10.1016/0040-4039(80)80216-4
日期:1980.1
The reaction of diphenyldiazomethane with 2,3-dichloro-5,6-dicyano-benzoquinone in the presence of alcohols and thiols gave the corresponding benzophenone acetals and thioacetals at 20–25°C in 1,2-dichloro-ethane. The mechanism of the reaction will be discussed.
Anodic desulfurization of dithioacetals of ketones in the presence of Et3N·3HF provided the corresponding gem-difluorocompounds while dithioacetals of aromatic and aliphatic aldehydes gave gem-difluoro thioethers and monofluoro thioether, respectively.
Selenonium ionic liquid as an efficient catalyst for the synthesis of thioacetals under solvent-free conditions
作者:Eder J. Lenardão、Elton L. Borges、Samuel R. Mendes、Gelson Perin、Raquel G. Jacob
DOI:10.1016/j.tetlet.2008.01.096
日期:2008.3
tetrafluoroborate, [BEPSe]BF4, was successfully employed as a catalyst for the synthesis of several dithioacetals in the absence of a solvent. The method is general and selectively afforded thioacetals derived fromaldehydes and ketones in good yields.
Green, catalyst-free thioacetalization of carbonyl compounds using glycerol as recyclable solvent
作者:Gelson Perin、Luzia G. Mello、Cátia S. Radatz、Lucielli Savegnago、Diego Alves、Raquel G. Jacob、Eder J. Lenardão
DOI:10.1016/j.tetlet.2010.06.049
日期:2010.8
We describe herein the use of glycerol as an efficient and a recyclablesolvent in the thioacetalization of aldehydes and ketones. The catalyst-free reactions proceed easily usingglycerol at 90 °C and the corresponding thioacetals were obtained in good to excellent yields. Glycerol was recovered and utilized for further thioacetalization reactions.
up: The selective electrochemical fluorination of organiccompounds using the alkali‐metal fluoride KF under very mild reaction conditions has been accomplished (see scheme). The long‐standing problems of low solubility of metal fluorides in organic solvent and low nucleophilicity of fluoride ions for fluorination have been overcome by the use of of poly(ethylene glycol).