Chemical and Pharmaceutical Bulletin p. 6 - 11 (1998)
Update date:2022-08-02
Topics:
Miyashita, Akira
Suzuki, Yumiko
Okumura, Yoko
Iwamoto, Ken-Ichi
Higashino, Takeo
When α-benzylbenzoin (3a, α-benzyl-α-hydroxybenzyl phenyl ketone) was treated with potassium cyanide (1) in N,N-dimethylformamide at 80°C for 1h, the carbon-carbon bond was cleaved, resulting in the formation of deoxybenzoin (4a, benzyl phenyl ketone) and benzaldehyde (2a). This carbon- carbon bond cleavage proceeds through a retro-benzoin condensation mechanism. This method of synthesizing ketones was applied to several α-substituted benzoins (3), and the corresponding ketones (4) were formed in good yields. Further, we found that the cyanide ion-donating ability of tetrabutylammonium cyanide (6, Bu4NCN) is more effective than that of potassium cyanide (1, KCN). As expected from the chemical analogy between cyanide ion and azolium ylide, several azolium salts (7) can also be employed in the retro-benzoin condensation as catalysts. The benzoin derivatives 3 were synthesized in the following three ways; reaction of alkyl halide (9) with benzoin (5), Michael addition of benzoin (5) with acceptors (10), and Grignard reaction of benzils (8). Alkylation of the benzoins without isolation, followed by carbon-carbon bond cleavage, readily afforded the corresponding ketones (4).
View MoreContact:+86-575-82733999 0575-82732999
Address:hangzhou gulf fine chemical zone,shangyu city,zhejiang province
Hangzhou Bayee Chemical Co.,Ltd.
Contact:+86-571-86990109
Address:No.380, Jiangnan Auenue, Binjiang District, Hangzhou, China
Zhonghao (dalian) Research and Design Institute of Chemical Industry Co., Ltd
Contact:+86 411 84674606
Address:201, Huangpu Road , Shahekou District, Dalian ,116023-China
Antaeus Bio-technology Co., LTD
Contact:021-31252569
Address:shanghai pudong
Liaoning Yufeng Chemical Co.,Ltd.
Contact:86-0419-3418888
Address:The metallurgical industrial zone,shoushan town, Liaoyang, Liaoning, China
Doi:10.1016/S0008-6215(00)84840-5
(1974)Doi:10.1002/jps.2600630910
(1974)Doi:10.1021/jm020485x
(2003)Doi:10.1039/P19740001112
(1974)Doi:10.1021/ja01216a042
(1946)Doi:10.1557/mrs2001.156
(1946)