| Summary: | 碩士 === 國立中正大學 === 化學研究所 === 88 === (1) Microwave Accelerated α-Methylenation of Ketone
Have the salt that mixed by diethylamine (Et2NH) and dibromomethane (CH2Br2) react with aldehyde compounds, a very good yield will show while -methylene reaction undergoes in room temperature. Unfortunately, it takes quite a lot of time to complete the reaction with ketone compounds of relatively poor reactiveness. On account of microwave techniques has contributed remarkable efficiency in organic reaction, we decided to modify the method by microwave irradiation to accelerate the reaction. This result in a wide margin of reactive efficiency of -methylene reaction with the salt mixed by diethylamine and dibromomethane, moreover, the time for reaction has shortened. Generally, it has a good reactive yield with aromatic aliphatic ketones; however, an electron-withdrawing group at -site is necessary for a successful -methylene reaction with dialiphatic ketones.
(2) Microwave Accelerated ο-Naphthoquinonemethide Formation
and Their [4+2] Cycloaddition Reaction
The salt that mixed by diethylamine (Et2NH) and dibromo-methane (CH2Br2) can successfully react with ozonide, aldehyde even ketone compounds. Nowadays, it can be applied in the preparation of Mannich base for phenolic compounds. Additionally, reaction of 2-naphthol with diethylamine and duterodichloromethane can induce deuteromethylene group in compound 178 successfully.
Now we have the products from Friedel-Crafts alkylation adduct which are from the reaction that the salt mixed by dibromomethane and diethylamine react with dienophile of electron-rich in condition of microwave, Hetero-Diels-Alder reaction will be prosecuted. It has been found that by means of the above mentioned, heterocyclic compounds can be easily synthesized, and a very good yield brought out as well.
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