Title:
【発明の名称】ラセミ化合物の2-(6-メトキシ-2-ナフチル)プロピオン酸またはその前駆物質の製造
Document Type and Number:
Japanese Patent JP2001508063
Kind Code:
A
Abstract:
In producing (+/-)-2-(6-methoxy-2-naphthyl)propionic acid or precursor thereof from 2-bromo-6-methoxynaphthalene, use is made of 2-bromo-6-methoxynaphthalene formed by (a) methylating 6-bromo-2-naphthol with methyl chloride in a solvent comprising one or more compounds, RZ, where R is a hydrogen atom or an alkyl group, and Z is -OH or -CN provided that if Z is -CN, R is alkyl, and in the presence of a strong base; and (b) recovering and purifying 2-bromo-6-methoxynaphthalene so formed. Preferably, the 6-bromo-2-naphthol is formed by (1) reacting 1,6-dibromo-2-naphthol with hydrogen, in a solvent comprising (a) organic halide in which the halogen has an atomic number of 35 or less or (b) a mixture of water and such organic halide, and in the presence of catalytically effective amounts of (i) a tungsten carbide-based catalyst, and (ii) phase transfer catalyst; and (2) separating 6-bromo-2-naphthol from the organic halide solvent so that the 6-bromo-2-naphthol is substantially free of halogen-containing impurities before use in the above methylation reaction. This technology makes possible reductions in quantities of co-products formed, eliminates need for use of excess iron and/or dimethyl sulfate as reaction components, and makes possible improvements in plant operating efficiency. Precursors of (+/-)-2-(6-methoxy-2-naphthyl)propionic acid formed from such 2-bromo-6-methoxynaphthalene are Grignard reagent of 2-bromo-6-methoxynaphthalene, bis(6-methoxy-2-naphthyl)zinc, 6-methoxy-2-naphthylzinc halide, 6-methoxy-2-naphthyllithium, 6-methoxy-2-naphthylcopper(I), bis(6-methoxy-2-naphthyl)cadmium, 6-methoxy-2-naphthylcadmium halide, and 6-methoxy-2-vinylnaphthalene.
Inventors:
Sabahi, Mahmoud
Kevin Jay, Serioto
Beckner, Brian Ef
Kevin Jay, Serioto
Beckner, Brian Ef
Application Number:
JP53093698A
Publication Date:
June 19, 2001
Filing Date:
December 29, 1997
Export Citation:
Assignee:
Albemarle Corporation
International Classes:
C07B61/00; C07C29/58; C07C37/00; C07C39/38; C07C41/09; C07C41/16; C07C41/30; C07C41/40; C07C41/42; C07C43/215; C07C43/225; B01J31/34; C07C51/09; C07C51/14; C07C59/64; C07C59/72; C07C67/343; C07C69/734; C07F3/02; C07F3/06; (IPC1-7): C07C51/14; B01J31/34; C07B61/00; C07C39/38; C07C41/09; C07C43/215; C07C51/09; C07C59/72; C07C67/343; C07C69/734; C07F3/02
Attorney, Agent or Firm:
Heiyoshi Odashima (1 person outside)