Air Stable N-Heterocyclic Carbene-Carbodiimide ('NHC-CDI') Adducts: Zwitterionic Type Bulky Amidinates

Herein we report a library of N-heterocyclic carbene-carbodiimide (“NHC-CDI”) adducts i. e., zwitterionic type amidinates from the reaction between N,N’ -diaryl substituted symmetrical or unsymmetrical carbodiimide and N-heterocyclic carbene at room temperature conditions. Generally, normal amidinates are air and moisture sensitive; that can be achieved by the treatment of amidines with base under air and moisture free conditions. In contrast, these new zwitterionic type bulky amidinate compounds are neutral and air stable. All new 31 examples of “NHC-CDI” adducts were characterized by 1H, 13C{1H} and HRMS analyses. Further, six compounds were confirmed by single crystal X-ray structural analysis.