Synthesis and X-ray molecular structures of the silver( I ) amides [{Ag[µ-N(SiMe 3 ) 2 ]} 4 ] and [{Ag[µ-NCMe 2 (CH 2 ) 3 CMe 2 ]} 4 ]

The thermally stable silver(I) amides [{Ag(µ-NR2)}4](R = SiMe3) 1 and [{Ag(µ-NR′2)}4][NR′2= [graphic omitted]Me2] 2, prepared from AgNCO and Sn(NR2)2 or Sn(NR′2)2, or for 1 also from M(NR2)2(M = Pb or Yb) or [{Sn(µ-F)NR2}2], are centrosymmetric, tetranuclear clusters comprising a square of Ag atoms [mean Ag⋯Ag 3.001(2)Å for 1 and 2.995(2)Å for 2] linked by singly bridging amido groups [mean Ag–N 2.148(5)Å for 1 and ranging from 2.126(7) to 2.184(7)Å for 2], the (AgN)4 macrocycle being planar for 1 but puckered for 2, and the N–Ag–N′ and Ag–N–Ag′ arrangements being essentially linear and rectangular, respectively.