Abstract:
[PROBLEMS] To provide a process for producing optically active hydroxymethylated compounds in high yields at high stereoselectivity with broad substrate generality, and a catalyst for the production. [MEANS FOR SOLVING PROBLEMS] The process comprises reacting a silicon enolate represented by the general formula (1) with formaldehyde in either an aqueous solution or a mixed solvent of water and an organic solvent in the presence of a catalyst obtained by mixing a ligand consisting of a chiral bipyridine or an antipode thereof with Bi(OTf)3: (1) wherein R5 to R7 are each hydrogen, an aliphatic hydrocarbon group, an aliphatic mono- or poly-cyclic hydrocarbon group, a mono- or poly-cyclic aromatic or araliphatic hydrocarbon group, or a heterocyclic group with the proviso that R5 and R7 are different from each other and R6 is not hydrogen; and R8's may be the same or different and are each methyl, ethyl, or isopropyl.
Abstract:
A method for an aldol reaction in water, characterized in that an aldehyde and an silyl enol ether is reacted in water as a medium in the presence of a boronic acid represented by the general formula (1): R R BOH (1) wherein R and R are hydrocarbon groups which may be the same or different and may have a substituent, a surfactant and a Brfnsted acid. The method for an aldol reaction in water allows the production of a product with high selectivity in high yield by the use of a boron source in an catalytic amount.
Abstract:
A silicon enolate represented by the following formula (Formula 1)
(in the formula, R 5 to R 7 represent hydrogen atoms, aliphatic hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, monocyclic or polycyclic aromatic or aromatic-aliphatic hydrocarbon groups or heterocyclic groups, R 5 and R 7 are different, R 6 is not a hydrogen atom, each R 8 may be identical or different and represents a methyl group, ethyl group or isopropyl group) and formaldehyde are allowed to react in an aqueous solution or a mixed solvent of water and an organic solvent in the presence of a catalyst obtained by mixing a ligand comprising a chiral bipyridine compound or its antipode and Bi(OTf) 3 .
Abstract:
The present invention presents a catalyst that allows asymmetric hydroxymethylation reactions to progress with excellent asymmetric selectivity and a production method for optically active hydroxymethylated compounds using the catalyst. Optically active hydroxymethylated compounds are obtained with excellent asymmetric selectivity by using a catalyst obtained by mixing chiral ligands (for example, chemical formula 4)