REACTIONS OF BIS(TRIMETHYLSILYL)AMINO-SUB STITUTED CHLOROSILANES [(ME3SI)(2)N]ME2-NPHNSICL (N = 0, 1, 2) WITH LITHIUM - SYNTHESIS OF BIS(TRIMETHYLSILYL)AMINO-SUBSTITUTED SILYL LITHIUM COMPOUNDS AND DISILANES

The bis(trimethylsilyl)amino-substituted chlorosilanes [(Me3Si)(2)N]Me 2-nPhnSiCl (1: n = 0, 2: n = 1, 3: n = 2) were allowed to react with l ithium metal in tetrahydrofuran. 1 slowly reacts at room temperature t o the homocoupling product {[(Me3Si)(2)N]Me2Si}(2) (4). An equimolar m ixture of 1 and Me3SiCl gives 4 and the cross-coupling product [(Me3Si )(2)N]Me2Si-SiMe3 (5). The reaction of 2 at -78 degrees C leads to for mation of bis(trimethylsilyl)aminosilyllithium [(Me3Si)(2)N]MePhSiLi ( 6), which reacts with Me3SiCl and 2 resp. to the corresponding disilan es [(Me3Si)(2)N]MePhSi-SiMe3 (7) and {[(Me3Si)(2)N]MePhSi}(2) (8). 6 u ndergoes partially self-condensation at -40 and 0 degrees C and the di silanyllithium [(Me3Si)(2)N]MePhSi-SiMePhLi (9) is formed. 3 reacts ra pidly at 0 and -20 degrees C to give the silyllithium [(Me3Si)(2)N]Ph2 SiLi (12). Treatment of 12 with Me3SiCl and 3 resp. affords the disila nes [(Me3Si)(2)N]Ph2Si-SiMe3 (13) and {[(Me3Si)(2)N]Ph2Si}(2) (14). Th e disilane R[(Me3Si)(2)NMeSi-SiMe3 (11) (R = 3,4,5,6-tetrakis(trimethy lsilyl)cyclohex-1-enyl) is obtained by reaction of a mixture of 2 and Me3SiCl in molar ratio 1:5 with 6 equivalents of lithium in THF. The c rystal structure of 11 is reported.