Ultrasound assisted remote functionalization of non-activated carbon atoms:: efficient in situ formation of tetrahydrofurans by sonolysis of bromohydrins with (diacetoxyiodo)benzene/I2

被引:20
作者
Costa, SCP [1 ]
Moreno, MJSM [1 ]
Melo, MLSE [1 ]
Neves, ASC [1 ]
机构
[1] Univ Coimbra, Fac Farm, Ctr Estudios Farmaceut, Quim Farmaceut Lab, P-3000 Coimbra, Portugal
关键词
steroids; tetrahydrofurans; halohydrins; sonochemistry;
D O I
10.1016/S0040-4039(99)01849-3
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
Ultrasonic irradiation of bromohydrins in the presence of (diacetoxyiodo)benzene and It generates alkoxyl radicals which lead in situ to intramolecular hydrogen abstraction on the C-19 non-activated carbon atoms in steroids producing tetrahydrofurans selectively in very good yields. Photolysis was less effective in promoting such conversions. (C) 1999 Elsevier Science Ltd. All rights reserved.
引用
收藏
页码:8711 / 8714
页数:4
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