Reactions of secondary silanes with biguanide bases: synthesis and characterizationof oligomeric 1,4-bis(silyl)biguanides and 1-alkyl-2,5-bis(silyl)biguanides

摘要

The reactions between diorganosilanes, R~1R~2SiH_2 (R~1 = Ph, R~2 = Ph or Me), and biguanide, 1-propylbiguanide or 1-cyclohexylbiguanide proceed via SiH/NH dehydrocoupling to afford the corresponding ohgomeric 1,4-bis(silyl)-biguanides (1,4) and 1-alkyl-2,5-bis(silyl)biguanides (2,3,5) with the general formula [R~1R~2SiNHC(NH)NC-(NHSiR~1R~2H)NR~3]_n {where R~1 = R~2 = Rh; R~3 = H (1), Pr~n (2) or Cy (3). R~1 = Me, R~2 = Ph: R~3 = H(4) or Pr~n (5)}. The IR and NMR spectra suggest the presence of differnt conformers in these compounds.