Novel axially chiral Rh N-heterocyclic carbene complexes were prepared from axially dissymmetric 1,1'-binaphthalenyl-2,2'-diamine and applied in the Rh-catalyzed enantioselective hydrosilylation of methyl ketones. The corresponding sec-alcohols can be obtained in high yields with good to excellent ee.

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Spirocyclic compounds containing an Si(N)4 core have been prepared from 1,2‐ethane‐ and 1,3 propanediamines bearing the electron‐withdrawing p‐toluenesulfonyl groups at the four N atoms. According to the X‐ray structure analysis of the compounds 8a and 13, the spirocyclic rings are almost perpendicular to each other. In both cases a distorted dodecahedral arrangement of a [4 + 4] octacoordinate Si atom is found in which one O atom of each of the four sulfonyl groups caps one of the planes defined by the Si(N)4 tetrahedron. The O···Si distances are 2.85–3.02 Å and the two O···Si···O angles are 145–159°. According to the X‐ray structure analysis of the monocyclic compound 16, one O atom of the p‐toluenesulfonyl group caps the plane defined by O1–N2–C13 of the distorted S(N2)(O)C tetrahedron.

Axially chiral thioamide ligands L5, L6, L8, L11, and bis(thioamide) ligand L13 were prepared from the reaction of (S)-(-)-1,1'-binaphthyl-2,2'-diamine with acyl chlorides and phosphorus pentasulfide (P2S5). The catalytic asymmetric 1,4-addition of diethylzinc to alpha,beta-unsaturated ketones was examined using this novel chiral ligand system with 28-73% ee in moderate to good yields.

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C(2)-Symmetric chiral diethoxyphosphoramide 4, diethoxythiophosphoramide 5, and diisopropoxyphosphoramide 6 of (1R, 2R)-1,2-diaminocyclohexane were prepared by the reactions of diethoxyphosphinic chloride, diethoxythiophosphinic chloride, and diisopropoxyphosphinic chloride with (1R, 2R)-1,2-diaminocyclohexane, respectively. They were used as catalytic chiral ligands in the asymmetric addition reactions of diethylzinc to aldehydes in the presence of titanium(IV) isopropoxide to give the corresponding sec-alcohols with 43-70% ee. Chiral ligands 4 and 5 gave the sec-alcohols with opposite absolute configuration.

chiral l&d (R)-N, N'-Bs(Zhydroxy-3,5-di-&ri-b~tyl-arylmethyl)-l, I'-binaphthalene2,2'-diamine derived from the reduction of schiff base ( R ) -2 , 2 ' -b~ (3,5-di-teri-butyl-%hyhxybenzylideneamino)-l, l'-bnaPhthyl with LiALH, is fairly effective in the asyrmnetric addition reaction of diethyizioc to aldehyder by which good yields (46%-94%) of the correspondiog sec-alcohols can be obtained in moderate ee (51%-79 % ) with R configuration for a variety of aldehydes. Keywordsa d l y dissymmetric chid ligand, ( R ) -N, N'-bis-(2-hyd~my-3,5-di-le~t-butyl-qhethyl)-1, I'-binaphthalene2,2'diamine, diethylzinc, asymmetric addition reaction *

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