Triorganostibines and -bismuthines ER3' as well as tetraorganodistibines and -dibismuthines E2R4' (E = Sb, Bi) react with trialkylalanes, -gallanes and -indanes R3M (M = Al, Ga, In) under formation of simple Lewis acid-base adducts of the type R3M-ER3' and bisadducts of the type [R3M](2)[E2R4']. Their structures and stabilities were investigated by single crystal X-ray diffraction, NMR spectroscopy and theoretical calculations. In addition, general pathways for the synthesis of heterocycles [R2MSbR2'](x) will be presented. Stibinogallanes and -indanes can generally be prepared by dehalosilylation reactions, while stibinoalanes are formed by dehydrosilylation reactions. This particular pathway is also applicable for the synthesis of [Me2AlBi(Tms)(2)](3). In addition, MSb heterocycles (M = Al, Ga, In) can be synthesized by reaction of tetraorganodistibines and trialkylalanes, -gallanes and -indanes. Monomeric compounds R2MER2' and RMER' (M = Al, Ga; E = Sb, Bi) have not been reported to date, but Lewis base-stabilized monomers of the type base-M(R-2)ER2' (M = Al, Ga; E = P, As, Sb, Bi) are formed by reaction of the corresponding heterocycle with 4(dimethylamino)pyridine (dmap). So prepared monomers react with transition metal complexes to give bimetallic complexes of the type base-M(R-2)ER2'-M(CO)(n).