N,N-bis-(dimethylfluorosilylmethyl)amides of N-organosulfonylproline and sarcosine: synthesis, structure, stereodynamic behaviour and in silico studies

摘要

(O→Si)-Chelate difluorides RRNCH(R)C(O)N(CHSiMeF) (, RR = (CH), R = Ms (a), Ts (b); R = H, R = Me, R = Ms (c)), containing one penta- and one tetracoordinate silicon atoms were synthesized by silylmethylation of amides RRNCH(R)C(O)NH, subsequent hydrolysis of unstable intermediates RRNCH(R)C(O)N(CHSiMeCl) () into 4-acyl-2,6-disilamorpholines RRNCH(R)C(O)N(CHSiMeO) () and the reaction of the latter compounds with BF·EtO. The structures of disilamorpholines , and difluoride were confirmed by an X-ray diffraction study. According to the IR and NMR data, the O→Si coordination in solutions of these compounds was weaker than that in the solid state due to effective solvation of the Si–F bond. A permutational isomerisation involving an exchange of equatorial Me groups at the pentacoordinate Si atom in complexes was detected, and its activational parameters were determined by H DNMR. estimation of possible pharmacological effects and acute rat toxicity by PASS Online and GUSAR Online services showed a potential for their further pharmacological study.