Chemistry of thermally stable bis(amino)silylenes

This paper provides a comprehensive review of the chemistry of the thermally stable bis(amino)silylenes Si[(NCH2But)2C6H4-1,2] [abbreviated as Si(NN)] 1 and Si[N(But)CH]2 [abbreviated as Si(N′N′)] 2 and the somewhat less stable Si[N(But)CH2]2 [abbreviated as Si(N″N″)] 3. In a brief introduction, comments are made on the importance of transient silylenes in organosilicon chemistry and on thermally stable mononuclear silicon(II) compounds having a coordination number greater than two for silicon. The chemistry of 1–3 is discussed under the headings: synthesis, molecular and electronic structures, and reactions. The latter are classified into eight categories: (i) nucleophilic additions to an unsaturated organic substrate; (ii) insertions (oxidative addition reactions to the silylene) into a compound containing a OH, CCl, CBr, CI or BC bond; (iii) insertions into a main group element compound having a MN (M=Li, Na, K), LiC, LiSi, or M′(II)X (M′=Ge, Sn or Pb; X=C, N, O or Cl) bond; (iv) insertions into a transition metalX bond; (v) further (see ii) oxidative addition reactions of a chalcogen or ButNC; (vi) reduction reactions; (vii) silylenes as ligands in transition or 4f block metal chemistry, and (viii) silylenes as electrophiles.