Journal fur Praktische Chemie - Chemiker-Zeitung p. 47 - 50 (1996)
Update date:2022-08-11
Topics:
Kaupp, Gerd
Sailer, Klaus
Multiple methylenations of 2-aminomethylbenzimidazole with dichloromethane and methylamine or ammonia or with hexamethylenetetramine lead to highly selective formations of 6 new single bonds to give only a polycyclic bis-spiro-1,5-diazocine 2 or only a polycyclic spiro-1,3,6-triazonine 4 or only a polycyclic 1,3,6,8-tetrazecine derivative 6. 4 and 6 may be equally well obtained starting with 2-chloromethyl-benzimidazole. All of these selectively formed products are concave cryptands with 6 amino nitrogen atoms. No template metals are used in their syntheses. The reasons for the unusual changes in selectivity are investigated using semi-empirical PM3 calculations and mechanistic considerations. Experimental and spectroscopic details are given. Johann Ambrosius Barth 1996.
View MoreDoi:10.1021/ac801699g
(2008)Doi:10.1080/00397910008087420
(2000)Doi:10.1021/acs.joc.7b00600
(2017)Doi:10.1016/S0040-6031(97)00264-5
(1997)Doi:10.1021/ja01145a072
(1951)Doi:10.1016/S0009-2614(01)01369-0
(2002)