Zinc catalyzed chemoselective hydrofunctionalization of cyanamides.

The zinc-catalyzed hydrosilylation and hydroboration of cyanamides have been described. Chemoselective reduction of cyanamides with PhSiH and partial or complete hydroboration of cyanamides with pinacolborane (HBpin) have been successfully carried out. The active catalyst/intermediate in the catalytic reactions, , the bis-guanidinate zinc amidinate compound, has been isolated and structurally characterized.

Gallium Hydride-Catalyzed Selective Hydroboration of Unsaturated Organic Substrates.

The first examples of tetrasubstituted conjugated bis-guanidinate (CBG) supported monomeric and thermally stable gallium dihalides [LGaX], (X=Cl (Ga-Cl), I (Ga-I)) and dihydride (Ga-H) [LGaH] (where L={(ArHN)(ArN)-C=N-C=(NAr)(NHAr)}; Ar=2,6-Et-CH) compounds are reported. The reaction of in situ generated LLi with 1.0 equiv.

Synthesis of low oxidation state zinc(I) complexes and their catalytic studies in the dehydroborylation of terminal alkynes.

A new example of a structurally characterized conjugated bis-guanidinate (CBG) supported zinc(I) dimer, , LZnZnL (3) (L = {(ArNH)(ArN)-CN-C(NAr)(NHAr)}; Ar = 2,6-Et-CH) with a Zn-Zn bond is reported. Moreover, homoleptic (3) and heteroleptic (Cp*ZnZnL, 2, (Cp* = 1,2,3,4,5-pentamethyl cyclopentadienide)) zinc(I) dimers are used as precatalysts in the dehydroborylation of a wide array of terminal alkynes. Furthermore, the active catalyst, CBG zinc acetylide (LZn-CC-Ph-4-Me), (5), is isolated which is confirmed by X-ray crystal structure analysis.