The synthesis of CF3C(O)NH(SnMe(3)) (1), CH3C(O)NR(SnMe(3)) (2, R = H; 3, R = Me; 4, R = Ph) and CH3C(O)N(SnMe(3))(2) (5) are reported. The IR and NMR (H-1, C-13, Sn-119) spectra are consistent with strong dominance of the planar amidate (rather than an imidate) tautomer. The Sn-119 NMR spectra of 1-5 are temperature invariant. The structures of 3 and 5, determined by X-ray means, revealed the presence of an intramolecular Sn- - -O interaction in which the SnMe(3) group is cis to the carbonyl, and an intermolecular O- - -Sn interaction which is stronger. Comparison of the solution and solid state Sn-119 NMR chemical shifts of 3 and 5 indicates that both types of Sn- - -O interactions are more robust in the solid state, Crystallographic data for 3 : space group P2(1)/n, a = 9.866 (3) Angstrom, b = 9.574 (4) Angstrom, c = 9.881 (3) Angstrom, alpha = 90 degrees, beta = 98.90 (1)degrees, gamma = 90.0 degrees, V = 922.1 (6) Angstrom(3); R = 0.0284. Crystallographic data for 5 : space group P2(1)/n, a = 6.898(1) Angstrom, b = 16.884(1) Angstrom, c = 11.222(3) Angstrom, alpha = 90.0 degrees, beta = 94.54(1)degrees, gamma = 90.0 degrees, V = 1302.9(4) Angstrom(3), R = 0.025.