一、A novel 1,8-addition of Grignard reaction to 1,1-diphenyl nitroethylene derivatives二、One-pot synthesis of bicyclonitrobischroman derivatives

• Main Authors: Wen-Chang Chen, 陳文章
• Other Authors: Ching-Fa Yao
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/11883299984639057031

博士 === 國立臺灣師範大學 === 化學系 === 104 === Abstract This thesis consists of two independent parts. Independently, each part has its own preface, motivation, discussion, experimental results, and conclusions. Research and discussion for the mechanism of the reaction between the Grignard reagent and β-nitrostyrene derivatives are discussed in the first section. Polar addition or single electron transfer has been a controversial issue in the Grignard reaction pathway. The previous studies showed the Grignard reagent with greater steric-hindered functionality, such as t-BuMgCl in polar solvent including THF, favors the SET reaction route; while the Grignard reactions with less steric crowding in non-polar solvents, such as ether were found to be via the polar addition route. The results of reactions of 1,1,2-triphenyl-2-nitroethane or β-nitrostyrene derivatives with several different kinds of Grignard reagents were discussed in this research work. Under -25℃inTHF, two different products were found to be 1,4-addition product via polar addition route and 1,8-addition product via single transfer electron route. 1,8-Addition product resulting from the Grignard reaction is novel since hitherto was not described. One-pot preparation of Chroman is the subject of the second part of this thesis. This one-pot synthesis was carried out under the following reaction condition to produce 3-nitro-chroman as an exclusive product with excellent yield. As such, salicylicaldehyde and cyclohexylamine along with nitromethane in (4:5:1) mixed in glacial acetic acid (2.0 ml) at 80-90℃for 24 hours. Therefore, a novel method for the preparation of Chroman was invented. Key word: polar addition、Single Electron Transfer、1,1,2-Triphenyl-2-nitroethene、Chroman