The approximate rate constants for 5-exo and 6-exo cyclizations of alk
yl radicals onto imines have been kinetically determined to be 6.0x10(
6) s(-1) and 6.7x10(5) s(-1) at 80 degrees C, respectively. Alkyl radi
cal additions to imines were essentially irreversible and considerably
slower than alkyl radical additions to hydrazones. Copyright (C) 1996
Elsevier Science Ltd