Arylthiazylamides:Syntheses,Structures,and Bonding Properties

摘要

Air-sensitive,thermally unstable tris(dimethylamino)sulfonium (TAS) salts (3) of the title anions [ArNSN]~- have been prepared from corresponding sulfurdiimides Ar-N=S=N-SiMe_3(2) by Si-N bond cleavage with [Me_2N)_3S]~+[Me_3SiF_2]~-(TASF).They are characterized by low-temperature X-ray crystallography as Z isomers.Because of the very short terminal S-N distance (144.2 (3h)-147.9 (3i) pm) and the relatively long internal S-N distance (158.3 (3i)-106.3 (3c) pm the [ArNSN]~- ilns should be regarded as thiazylamides 1b,rare species containing a S ident to N triple bond.A bonding model is developed and the experimental results are compared with those of restricted Hartree-Fock (RHF),density functional theory (DFT),and M#PHI# ller -Plesset second-order (MP2) calculations.