摘要:
trans-RuH(&eegr;1-BH4)[(S)-xylbinap][(S,S)-dpen] (0.00125 mmol), acetophenone (5.0 mmol), and 2-propanol (2.5 mL) were placed in an autoclave, and the resulting solution was repeatedly subject 5 times to a procedure of performing pressure reduction and argon introduction while stirring the solution for deaeration. A hydrogen tank was then connected to the autoclave, and after replacing the air inside an introduction tube with hydrogen, the pressure inside the autoclave was adjusted to 5 atmospheres and then hydrogen was released until the pressure dropped to 1 atmosphere. After repeating this procedure 10 times, the hydrogen pressure was adjusted to 8 atmospheres and stirring at 25° C. was performed for 12 hours. By concentrating the solution obtained by depressurization and subjecting the crude product to simple distillation, (R)-1-phenylethanol (yield: 95%) in the form of a colorless oily substance was obtained at an ee of 99%.
摘要:
The present invention provides a catalyst for transesterification comprising an organotin compound expressed by the following general formula (I): ##STR1## wherein, X, Y, and Z represent, respectively and independently, an alkoxyl group, alkylthio group, halogen atom, or alkyl group; where at least two groups among X, Y, and Z represent an alkoxyl group, alkylthio group, or halogen atom; R represents an organic chain; and R' represents a hydrogen atom, or alkyl group.
摘要:
A process for preparing an optically active alcohol is disclosed, which comprises asymmetrically hydrogenating a carbonyl compound in the presence of a ruthenium-optically active phosphine complex as a catalyst. The resulting alcohol has high optical purity.
摘要:
Disclosed is a method for producing an alcohol from a lactone or a carboxylic acid ester, which enables to produce an alcohol from a lactone or a carboxylic acid ester under relatively mild conditions with high yield and high catalytic efficiency. This method also enables to produce an optically active alcohol from an optically active lactone or an optically active carboxylic acid ester. Specifically disclosed is a method for producing an alcohol by hydrogen reducing a lactone or a carboxylic acid ester in the presence of a catalyst containing ruthenium and a phosphine compound represented by the following general formula (1): wherein R1 represents a spacer; R2, R3, R4, R5, R6 and R7 independently represent a hydrogen atom, an alkyl group having 1-12 carbon atoms, an aryl group or a heterocyclic group; and R8, R9, R10, R11, R12 and R13 independently represent an alkyl group having 1-12 carbon atoms, an aryl group or a heterocyclic group.
摘要:
A novel ruthenium complex which is a highly efficient catalyst useful for the production of optically active 3-quinuclidinols, and a process for production of optically active 3-quinuclidinols using the ruthenium complex as a catalyst, where the optically active 3-quinuclidinols are useful as an optically active, physiologically active compound utilized in medicines and agrichemicals or as a synthetic intermediate such as a liquid crystal material.
摘要:
Methods and reagents for transition metal-promoted carbonylation via isocyanate using carbon-isotope labeled carbon monoxide are provided. The resultant carbon-isotope labeled compounds are useful as radiopharmaceuticals, especially for use in Positron Emission Tomography (PET). Associated kits for PET studies are also provided.
摘要:
The present invention provides a process for the production of PGD.sub.2, wherein 7-hydroxy prostaglandin F.sub.2 .alpha. is treated with thiocarbonyl diimidazole or its analog and subjecting thus treated product to the reaction to deoxidize the hydroxyl group at the 7-position, the reaction to convert the hydroxyl group to a protecting group, and the reaction to oxidize the hydroxyl group at the 11-position, thus giving PGD.sub.2 at a high efficiency.
摘要:
Novel 5-alkylidene-4-substituted-2-cyclopentenones and 5-(1-hydroxy-aliphatic hydrocarbon)-4-substituted-2-cyclopentenones.These novel cyclopentenones and 5-alkylidene-3-hydroxy-4-substituted cyclopentanones have a pharmaceutical activity for treatment of tumors.
摘要:
A ruthenium-phosphine complex having a 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl or its derivative as a ligand and carboxyl groups bonded to the ruthenium atom thereof is disclosed. The complex is inexpensive and exhibits excellent performances as a catalyst for various organic syntheses, and particularly for asymmetric hydrogenation.
摘要:
A 4-hydroxy-2-cyclopentenone represented by the following formula (I) ##STR1## wherein X represents a hydrogen or halogen atom, A represents a hydrogen atom and B represents a hydroxyl group, or A and B are bonded to each other to represent a bond, R.sup.1 represents a substituted or unsubstituted alkyl, alkenyl or alkynyl group having 1 to 10 carbon atoms, R.sup.2 represents a substituted or unsubstituted alkyl, alkenyl or alkynyl group having 1 to 10 carbon atoms, and R.sup.3 represents a hydrogen atom or a protective group for a hydroxyl group, provided that R.sup.2 is not a 2-octenyl, 8-acetoxy-2-octenyl or 2,5-octadienyl group. The compounds of formula (I) in which A is hydrogen and B is hydroxyl group are prepared by subjecting a 5-unsubstituted cyclopentenone and an aldehyde to aldol condensation reaction. The compounds of formula (I) in which A and B form a bond is prepared by subjecting the compounds of the formula (I) in which A is hydrogen and B is hydroxyl group to dehydration. The compounds (I) are useful for treatment of malignant tumors.