It has come to light: Renewed interest in conversions of highly oxygenated materials has motivated studies of the organometallic-catalyzed photocatalytic dehydrogenative decarbonylation of primary alcohols into alkanes, CO, and H(2). Methanol, ethanol, benzyl alcohol, and cyclohexanemethanol are readily decarbonylated. The photocatalysts are also active for amine dehydrogenation to give N-alkyl aldimines and H(2).

The achiral and enantiopure chiral compounds To M Rh(CO) 2 (3) and To P Rh(CO) 2 (4) (To M = tris(4,4-dimethyl-2-oxazolinyl)phenylborate; To P = tris(4S-isopropyl-2-oxazolinyl)phenylborate) were prepared to investigate stereoselective oxidative addition reactions and develop new catalytic enantioselective bond functionalization and cross-coupling chemistry. Reactivity at the rhodium center is first shown by the substitution of the carbonyl ligands in 3 and 4 in the presence of the appropriate ligand; thus treatment of To M Rh(CO) 2 with P(OMe) 3 provides To M Rh(CO)[P(OMe) 3 ] (5). However, reaction of To M Rh(CO) 2 and MeOTf (Tf = SO 2 CF 3 ) affords the complex [{N-Me-κ 2 -To M }Rh(CO) 2 ]OTf (6), resulting from N-oxazoline methylation rather than oxidative addition to rhodium(I). In contrast, To M Rh(CO) 2 reacts with allyl bromide and chloroform, forming the rhodium(III) species (κ 3 -To M )Rh(η 1 -C 3 H 5 )Br(CO) (7) and (κ 3 -To M )Rh(CHCl 2 )Cl(CO) (8), respectively. Interestingly, the chiral To P Rh(CO) 2 and CHCl 3 react to give one diastereomer of (κ 3 -To P )-Rh(CHCl 2 )Cl(CO) (9; 100:3 dr) almost exclusively. To evaluate the reactivity of these rhodium(I) compounds, the carbonyl stretching frequencies have been examined. The data for the mono-and trivalent rhodium oxazolinylborate compounds indicate that the electron-donating ability of [To M ] -is slightly greater than that of [To P ] -, and both ligands provide electronic environments that can be compared to the tris(pyrazolyl)borate ligand family.

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