Two Novel Thermal Biradical Cyclizations in Theory and Experiment: New Synthetic Routes to 6H-Indolo[2,3-b]quinolines and 2-Aminoquinolines from Enyne-Carbodiimides
作者:Michael Schmittel、Jens-Peter Steffen、Bernd Engels、Christian Lennartz、Michael Hanrath
DOI:10.1002/(sici)1521-3773(19980918)37:17<2371::aid-anie2371>3.0.co;2-n
日期:1998.9.18
The regioselectivity of the biradical cyclization of enyne-carbodiimides 1 can easily be controlled by variation of R1 at the alkyne terminus. Attachment of a hydrogen atom (R1 =H) leads to C2 -C7 cyclization and formation of biradical 2, whereas C2 -C6 cyclization to provide biradical 3 is observed with R1 =Me3 Si or Ph.
炔烃-碳二亚胺1的双自由基环化的区域选择性可以通过炔烃末端的R 1的变化轻松控制。氢原子的附着(R 1= H)导致C 2 -C 7环化并形成双自由基2,而在R 1= Me 3 Si或Ph下观察到C 2 -C 6环化以提供双自由基3 。