Yoji Hori

Ruthenium catalyzed selective synthesis of enol carbamates by fixation of carbon dioxide

Abstract Secondary amines react with carbon dioxide and terminal alkynes in the presence of a catalytic amount of 4-1,5-cyclooctadiene) (6-1,3,5-cyclooctatriene)ruthenium [Ru(COD)(COT)] and tertiary phosphine in toluene to give enol carbamates in good yields with high regio- and stereoselectivity. Cyclic enol carbamates, 5-methylene-2-oxazolidinones are obtained from N-substituted propargylamines and carbon dioxide in high yields.

Highly stereoselective asymmetric hydrogenation of 2-benzamidomethyl-3-oxobutanoate catalysed by cationic binap–ruthenium(II) complexes

Highly diastereoselective hydrogenation of methyl 2-benzamidomethyl-3-oxobutanoate has been accomplished by using [Rul{(R)-binap}(p-cymene)]I and corresponding complexes of derivatives of binap as catalyst, giving methyl (2S,3R)-2-benzamidomethyl-3-hydroxybutanoate, a versatile intermediate for the synthesis of β-lactam antibiotics, in up to 98% diastereoisomeric excess and 99% enantiomeric excess.

Novel organic syntheses catalyzed by (cyclooctadiene) (cyclooctatriene) ruthenium and its derivatives

Abstract The characteristic catalytic activities of low valence ruthenium complexes, (cyclooctadiene)(cyclooctatriene)ruthenium and its derivatives, in organic syntheses have been exhibited by reviewing the recently developed novel reactions; (1) the first linear co-dimerization of acetylenes with 1,3-dienes (2) the [2 + 2] cross cycloaddition of norbornenes with dimethyl acetylenedicarboxylate (3) the addition of carboxylic acid to acetylenes giving enol esters.

Ruthenium complex catalyzed selective addition of carboxylic acids to acetylenes giving enol esters

Carboxylic acids react with acetylenes in the presence of a catalytic amount of bis(η5-cyclooctadienyl)ruthenium-PR3-maleic anhydride in toluene to give enol esters in good to excellent yields with high regioselectivity.

Ruthenium-catalyzed addition reaction of acetic acid to propargyl alcohol derivatives: reagents for palladium-catalyzed 2-acetoxyallylation of carbonucleophiles

Abstract A bis(η 2 -cyclooctadienyl)ruthenium/PCy 3 /maleic anhydride system catalyzes the addition reaction of acetic acid to propargyl alcohol derivatives at 80°C to give 2-acetoxyallyl derivatives with high selectivity in high yields. The 2-acetoxyallyl carbonates prepared react with carbonucleophiles in the presence of a catalytic amount of Pd(PPh 3 ) 4 to give a series of novel polyfunctional enol esters in good to excellent yields.

Hutheniuh-catalyzed synthesis of p-ficetoxyallyl carbonates: A synthon for palladium-catalyzed 2-acetoxyallylation of carbonucleophiles

Abstract Propargyl carbonates react with acetic acid in the presence of a catalytic amount of bis(ν 5 -cyclooctadienyl)ruthenium/PCy 3 /maleic anhydride at 80°C to give 2-acetoxyallyl carbonates in good yields with excellent regioselectivity. These 2-acetoxyallyl carbonates catalytically react with carbonucleophiles in the presence of tetrakis(triphenylphosphine)palladium to give 2-acetoxyallylated products in good to excellent yields,