Scheme 4.
Reagents and conditions: a) Pd(OAc)2, (2-biphenyl)dicyclohexylphosphine, K3PO4, toluene, 90 °C 24 h; b) aminoguanidine hydrochloride, LiCl, EtOH, reflux, 24 h.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.