OPTICALLY ACTIVE QUATERNARY AMMONIUM SALT, PROCESS FOR PRODUCING THE SAME, AND PROCESS FOR PRODUCING OPTICALLY ACTIVE alpha-AMINO ACID DERIVATIVE WITH THE SAME

摘要

[PROBLEMS] To provide (1) an optically active quaternary ammonium salt which, when used as an asymmetric-axis-containing spiro type phase-transfer catalyst for the asymmetric alkylation of a glycine derivative, shows high stereoselectivity for substrates such as ones having a small molecular size, e.g., methyl iodide, and sec-alkyl halides; an optically active alpha-amino acid derivative produced stereroselectively and useful as an intermediate for medicines and agricultural chemicals; and a process for producing the derivative; and (2) a novel optically active quaternary ammonium salt which has high performance when used as an asymmetric-axis-containing spiro type phase-transfer catalyst for the asymmetric alkylation of a glycine derivative, and in which the rings constituting the spiro skeleton have the same structure, which is advantageous from the standpoint of the number of catalyst synthesis steps; a process for producing the salt; and a method of recovering the salt. [MEANS FOR SOLVEING PROBLEMS] (1) An asymmetric-axis-containing spiro type ammonium salt having an alkyl- or aryl-substituted silyl group introduced on an aromatic ring is used as a phase-transfer catalyst to conduct the asymmetric alkylation of a glycine derivative. (2) An asymmetric-axis-containing spiro type ammonium salt having introduced therein a substituent including a perfluoroalkyl group is used in the asymmetric alkylation of a glycine derivative and then recovered with a fluorous solvent.