Guanidine synthesis

Drake, B. Patek, M. Lebl, M. A Convenient Preparation of Monosubstituted yV,yV -di(Boc)-Protected Guanidines, Synthesis 1994, 579-582. 

When guanidines are used in place of amidines in the syntheses, the products are 2-amino-imidazoles or -imidazolines <82CHE185, 91M1063, 91TL5325, 92T6385). A mild and efficient method reported for guanidine synthesis should extend the scope of this approach (Scheme 172) <92TL5933>. 

Gers, T., Kunce,D., Markowski, P. and Izdebski, J. (2004) Reagents for efficient conversion of amines to protected guanidines. Synthesis, 37-42. 

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