Diverse reactivity of a boraguanidinato germylene toward organic pseudohalides

The reactions of the boraquanidinato germylene (i-Pr) 2 NB(NDmp) 2 Ge ( 1 ) (Dmp = 2,6-Me 2 C 6 H 3 ) with RN 3 and RNCS produced rare examples of Ge 2 N and Ge 3 S rings, while the treatment of 1 with RNCO led to an insertion into the N-Ge bond leading to a novel type of germylene stabilized within a six membered ring, i.e. [N(R)C(O)N(Dmp)B(N(i-Pr) 2 )N(Dmp)]Ge (R = t -Bu or Ad). The reactivity of the N , N -chelated germylene with pseudohalides was investigated producing various types of novel heterocycles.