摘要:
A method for racemization of optically active 2,2-dimethylcyclopropane-1-carboxylic acid by converting said acid to the corresponding halide thereof represented by the general formula; ##STR1## wherein X is a halogen atom, which is heated to a temperature of about 80.degree. C. to about 300.degree. C., preferably about 100.degree. C. to about 200.degree. C., and then, if desired, producing 2,2-dimethylcyclopropane-1-carboxylic acid by hydrolysis of the resultant acid halide.
摘要:
The present invention relates to a process for producing optically active halomethyl phenyl carbinols of the formula (1), comprising reducing halomethyl phenyl ketones of the formula (2) using an asymmetric reducing agent obtained from boranes and optically active .alpha.-phenyl-substituted-.beta.-amino alcohols of the formula (3) or optically active .alpha.-non-substituted-.beta.-amino alcohols of the formula (4). The present invention further relates to a process for producing optically active carbinols, comprising reacting a prochiral keytone with an asymmetric reducing agent obtained from optically active .beta.-amino alcohols of the formula (5), a metal boron hydride and Lewis acid or lower dialkyl sulfuric acid. All of the formulas (1) to (5) are the same as shown in the specification.
摘要:
A process for preparing an optically active alcohol by reacting a prochiral ketone corresponding to the optically active alcohol and an acid with a mixture of (1) a boron-containing compound selected from the group consisting of i) a borane compound which is obtained from an optically active .beta.-aminoalcohol and a boron hydride; or obtained from the optically active .beta.-aminoalcohol, a metal borohydride and an acid and ii) an optically active oxazaborolidine and (2) a metal borohydride; and a process for preparing an optically active amine by reacting an oxime derivative and an acid with a mixture of (1) a boron-containing compound selected from the group consisting of i) a borane compound which is obtained from an optically active .beta.-aminoalcohol and a boron hydride, or obtained from said optically active .beta.-aminoalcohol, a metal borohydride and an acid and ii) an optically active oxazaborolidine, and (2) a metal borohydride.
摘要:
The present invention provides a process for producing (R)-styrene oxides represented by the formula (1): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and X are as defined in the specification, which comprises treating a mixture of (R)- and (S)-phenylhalogenomethylcarbinols with a lipase in the presence of a carboxylate to preferentially convert the (S)-phenylhalogenomethylcarbinols, and treating a mixture of the formed carbinol alkylates (3) and (R)-phenylhalogenomethylcarbinols with a base to cyclize the (R)-phenylhalogenomethylcarbinols, and also provides an industrially excellent process for producing (R)-styrene oxides (1) which comprises using a mixture enriched with (R)-phenylhalogenomethylcarbinols as the mixture of (R)- and (S)-phenylhalogenomethylcarbinols (2).
摘要:
The present invention relates to a process for producing optically active halomethyl phenyl carbinols of the formula (1), comprising reducing halomethyl phenyl ketones of the formula (2) using an asymmetric reducing agent obtained from boranes and optically active .alpha.-phenyl-substituted-.beta.-amino alcohols of the formula (3) or optically active .alpha.-non-substituted-.beta.-amino alcohols of the formula (4).The present invention further relates to a process for producing optically active carbinols, comprising reacting a prochiral ketone with, an asymmetric reducing agent obtained from optically active .beta.-amino alcohols of the formula (5), a metal boron hydride and Lewis acid or lower dialkyl sulfuric acid. All of the formulas (1) to (5) are the same as shown in the specification.
摘要:
A process for preparing an optically active alcohol by reacting a prochiral ketone corresponding to the optically active alcohol and an acid with a mixture of (1) a boron-containing compound selected from the group consisting of i) a borane compound which is obtained from an optically active .beta.-aminoalcohol and a boron hydride; or obtained from the optically active .beta.-aminoalcohol, a metal borohydride and an acid and ii) an optically active oxazaborolidine and (2) a metal borohydride; and a process for preparing an optically active amine by reacting an oxime derivative and an acid with a mixture of (1) a boron-containing compound selected from the group consisting of i) a borane compound which is obtained from an optically active .beta.-aminoalcohol and a boron hydride, or obtained from said optically active .beta.-aminoalcohol, a metal borohydride and an acid and ii) an optically active oxazaborolidine, and (2) a metal borohydride.
摘要:
The present invention relates to an optically active borane complex represented by the general formula, ##STR1## wherein R.sup.1 represents an aryl group, R.sup.2 represents an alkyl group and a mark * means an asymmetric carbon, and a method for producing optically active alcohol derivatives by the reduction of prochiral ketones with said borane complex. The optically active alcohol derivative is useful for fungicides, herbicides or plant growth regulators.
摘要:
A method for producing an optically active amine which is an important compound as a resolving agent for medicines, agricultural chemicals, intermediates thereof, etc is disclosed.
摘要:
The optically active benzylamine derivatives of the present invention are very useful for use as the asymmetric ligand of an asymmetric reducing agent. By using the optically active amine-boron complex prepared from the compound of the present invention, optically active products can be obtained in a specifically high optical yield. Moreover, the separation and recovery of the reaction products and asymmetric ligand can be easily achieved.
摘要:
The present invention relates to an optically active borane complex represented by the general formula, ##STR1## wherein R.sup.1 represents an aryl group, R.sup.2 represents an alkyl group and a mark * means an asymmetric carbon, and a method for producing optically active alcohol derivatives by the reduction of prochiral ketones with said borane complex. The optically active alcohol derivative is useful for fungicides, herbicides or plant growth regulators.