Von N,N′ ‐Bis(1,1,3‐trisila‐2‐aza)‐ethylen‐diaminen zu N,N′ ‐Bis(1,3‐disila‐2‐lithiumamido)‐ethylensilylaminen – Synthesen, Kristallstrukturen, Reaktionen

From N,N′ ‐Bis(1,1,3‐trisila‐2‐aza)‐ethylene‐diamines to N,N′ ‐Bis(1,3‐disila‐2‐lithiumamido)‐ethylenesilylamines – Syntheses, Crystal Structures, Reactions Ethylenediamine reacts with the chloro‐functional tris(silyl)amines ClSiMe 2 N(SiMe 3 )SiMe 2 R in a molar ratio of 1:2 to give the N,N′ ‐bis(1,1,3‐trisila‐2‐aza)‐ethylenediamines, [CH 2 ‐NH‐SiMe 2 ‐N(SiMe 3 )SiMe 2 R] 2 , R = Me ( 1 ) and CMe 3 ( 2 ). A structural isomer of 2 (CH 2 ‐NSiMe 2 CMe 3 ‐SiMe 2 ‐NHSiMe 3 = 3 ) is formed thermally, via 1,3‐silyl group migration from the Me 3 CSiMe 2 ‐N‐SiMe 3 group, at 200 °C. 1 reacts with butyllithium at 0 °C in a molar ratio of 1:2, forming the diamide 4 , which was characterized as the monomer [CH 2 –NSiMe 3 –SiMe 2 –N(SiMe 3 )Li] 2 . Again two silyl groups migrate from the N(SiMe 3 ) 2 groups to the ethyleneamine nitrogen atoms. The lithium ions are coordinated by both amido groups forming a planar four‐membered ring. With THF as a solvent, each lithium ion of 4 coordinates one THF molecule. [CH 2 –NSiMe 3 –SiMe 2 –N–(SiMe 3 )Li–THF] 2 ( 5 ) is obtained. With TMEDA as the donor base the cage structures of 4 and 5 are broken up to give an open‐chain dilithium salt [CH 2 –NSiMe 3 –SiMe 2 –N(SiMe 3 )Li–TMEDA] 2 ( 6 ) with each lithium ion coordinated by one TMEDA molecule. Halosilanes and haloboranes react with 4 , 5 , and 6 to give an N,N′ ‐bis(1,1,3‐trisila‐2‐aza)‐ethylenesilylamine [CH 2 –NSiMe 3 –SiMe 2 –N(SiMe 3 )R] 2 , R = SiF 2 CMe 3 ( 7 ), and N,N′ ‐bis(1‐bora‐1,3‐disila‐2‐aza)‐ethylenesilylamines, R = B(F)N(SiMe 3 ) 2 ( 8 ), B(F)[N(CMe 2 CH 2 ) 2 CH 2 ] ( 9 ).