Diarylstannylene activation of hydrogen or ammonia with arene elimination
Yang Peng1, Bobby D Ellis, Xinping Wang
1Department of Chemistry, University of California Davis, One Shields Avenue, Davis, California 95616, USA.
Abstract:
Treatment of the stannylenes SnAr'2 (Ar' = C6H3-2,6(C6H3-2,6-Pri2)2), SnAr2# (Ar# = C6H3-2,6-(C6H2-2,4,6-Me3)2, or Sn{N(SiMe3)2}2 with H2, D2, or NH3 under identical, mild (1 atm, 65 degrees C) conditions showed that SnAr2' reacted readily to afford the products {Ar'Sn(mu-H)}2, {Ar'Sn(mu-D)}2, or {Ar'Sn(mu-NH2)}2 with elimination of Ar'H or Ar'D. The less crowded stannylenes SnAr2# and Sn{N(SiMe3)2}2 were recovered unreacted. The differences in reactivity were accounted for in terms of the n-p energy separations which is lowest in the case of AnAr2'. The low energy separation in SnAr' is consistent with enhanced singlet diradical character of the ground state which increases its reactivity.
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