Highly efficient synthesis of 1H-quinazoline-2,4-diones using carbon dioxide in the presence of catalytic amount of DBU
作者:Takumi Mizuno、Yoshio Ishino
DOI:10.1016/s0040-4020(02)00279-x
日期:2002.4
The first example of chemical fixation of carbon dioxide in the presence of catalytic amount of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) or DBN (1,5-diazabicyclo[4.3.0]non-5-ene) was developed. Carbon dioxide easily reacted with 2-aminobenzonitriles under mild conditions (1 atm, 20 degreesC), assisted by excess amount of DBU or DBN to give corresponding 1H-quinazoline-2,4-diones in excellent yields. Also, catalytic amount of DBU or DBN is effective for the synthesis of 1H-quinazoline-2,4-diones. Using catalytic amount of DBU (0.05 equiv.), 7-chloro- 1H-quinazoline-2,4-diones which is a key intermediate of medicines (FK366, Zenarestat(R) and K1731327) was synthesized successfully in a 90% yield under the CO2 pressure of 10 atm at 80degreesC. (C) 2002 Elsevier Science Ltd. All rights reserved.