Heterocyclic gallanes

These particular properties of chloroalanes favor the formation of simple Lewis acid-base adducts, as was observed for the reaction of R2AICI with Sb(Tms)3 (R = Et, f-Bu). In contrast, reactions of the analogous gallanes and indanes yielded the desired heterocycles. The same tendencies were observed in reactions of R2MCI (M = Al, Ga, In R = Et, i-Bu) with P(Tms)3 and As(Tms)3. The gallane and indane react under formation of the expected M—E heterocycles [71], while the corresponding alanes yield the simple adducts... 

Reactions of tetraalkyldistibines and -dibismuthines with trialkylalanes and -gallanes yield bisadducts of the type [R3M]2[E2R4]. These compounds are stable in the solid state, while they easily undergo consecutive reactions in solution. Completely alkyl-substituted heterocycles [R2MER x are formed under cleavage of the Sb—Sb bond, as was demonstrated for two Ga—Sb heterocycles. 

Syntheses, structures and properties of heterocyclic group 13/15 compounds of the type [R2M LR 2]V have been the subject of intense studies for many years. In particular, aminoalanes and -gallanes [IGIVINR/ (M = Al, Ga) have received considerable attention. The interest in these particular compounds has increased within the last two decades due to their potential application as single source precursors for the deposition of AIN and GaN... 

Heterocyclic stibino- and bismuthinoalanes, -gallanes and -indanes adopt structures in the solid state analogous to those observed for the corresponding amides, phosphides and arsenides. Their central structural parameters are summarized in Table XVIII. 

Monomeric compounds (x = 1) containing M=E double bonds remained unknown until Power and Roesky et al. reported in 2001 on the synthesis of the first monomeric iminoalane and -gallane by oxidative addition of an organoazide to a sterically encumbered low-valent A1(I) compound 4 This reaction type has been shown previously to yield heterocyclic compounds by use of sterically less hindered [Cp Al]4.145 Very recently, von Hanisch and Hampe synthesized the first GaAs compound featuring a Ga=As double bond5 (Scheme 19, Figs. 41 and 42). 

Wells et al. reported almost twenty years ago on the reactions of chloro-gallanes and trimethylsilyl-substituted arsanes R 2AsSiMe3, which occurred under elimination of MesSiCl and subsequent formation of arsinogallanes of the types [Cl2GaAsR 2]%> RGa(AsR2)2 and Ga(AsR2)3 [23]. In 1988, Cowley et al. extended this reaction type to the synthesis of heterocyclic stibinogal-lanes and -indanes [21]. 

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