α‐Isothiocyanatoacrylsäureester, VI. Notiz zur γ‐Bromierung von 2‐Isothiocyanato‐2‐butensäureestern und zur nachfolgenden nucleophilen Substitution

Note on the γ‐Bromination of 2‐Isothiocyanato‐2‐butenoates and Subsequent Nucleophilic Substitutions 2) 2‐Isothiocyanato‐2‐butenoates 1 and 5 are brominated by means of N ‐bromosuccinimid to yield γ‐bromo isothiocyanates 2 and 6 , respectively. The reaction of bromides 2 with nucleophiles predominantly proceeds by γ‐substitution or alternatively via a prior attack at the N = C = S group followed by cycloalkylation to provide 6H ‐l,3‐thiazine‐4‐carboxylates 9 .