Intramolecular “Hydroiminiumation and -amidiniumation” of Alkenes: A Convenient, Flexible, and Scalable Route to Cyclic Iminium and Imidazolinium Salts
作者:Rodolphe Jazzar、Jean-Baptiste Bourg、Rian D. Dewhurst、Bruno Donnadieu、Guy Bertrand
DOI:10.1021/jo0703909
日期:2007.4.1
induces ringclosure cleanly and regioselectively via formal “exo” addition of the nitrogen−hydrogen bond to the pendent carbon−carbon double bond, affording the corresponding cyclic aldiminium, dihydroisoquinolinium, and imidazolinium salts. Of special interest, novel 4,4-disubstituted imidazolinium salts are accessible via this synthetic route. Similarly, addition of phosgene to alkenyl ureas and alkenyl
We have developed I2‐ or N‐iodosuccinimide (NIS)‐mediated amidiniumation of N‐alkenyl formamidines for the syntheses of cyclic formamidinium salts, some of which could be directly used as N‐heterocyclic carbene (NHC) precursors. Treatment of iodine‐containing formamidinium salts with Al2O3 led to the formation of cyclic formamidinium salts with an unsaturated backbone. A rhodium(I) complex ligated