摘要:
The keto group at the 7-position of a bile keto acid is stereoselectively reduced to a beta-hydroxy group with hydrogen in the presence of nickel, a base (the quantity of which is at least 0.3 mole for each mole of keto acid), and an alcohol having from 3 to 10 C atoms, selected from the group consisting of secondary alcohols, tertiary alcohols and beta-branched alcohols.
摘要:
The acylation of a naphthalene compound, substituted in the 2-position with an electron-donating group, with a reactive derivative of a lower aliphatic acid, in an aprotic organic diluent and in the presence of a Friedel Crafts catalyst consisting of a halide of an element having at least two valences, is improved when maintaining constant at any time the molar ratio of the naphthalene compound to the acylating agent and that of the acylating agent to the Friedel Crafts catalyst within specific ranges.
摘要:
Process for preparing esters of 2-(6'-methoxy-2'-naphtyl)-propionic acid via rearrangement of new ketals of 2-halo-1-(6'-methoxy-2'-naphtyl)-propan-1-one in the presence of a Lewis acid.The esters thus obtained are useful as intermediate products for preparing Naproxen.The process involves the preparation of the following new compounds:ketals of 2-halo-1-(6'-methoxy-2'-naphtyl)-propan-1-oneesters of 2-(5'-bromo-6'-methoxy-2'-naphtyl)-propionic acid1-(5'-bromo-6'-methoxy-2'-naphtyl)-propan-1-one2-halo-(5'-bromo-6'-methoxy-2'-naphtyl)-propan-1-one.
摘要:
Preparation of aryl alkyl ketones by reaction of an aryl compound with an aliphatic acid and/or a functional derivative thereof in anhydrous hydrofluoric acid.
摘要:
Process for preparing an arylalkanoic acid by adding iodine to a mixture of an arylalkanone and an excess of an orthoester, heating of the mixture thus obtained, adding an inorganic base and finally an acid.
摘要:
Process for the optical resolution of (.+-.)2-(6'methoxy-2'-naphthyl)-propionic acid by adding from 0.45 to 0.65 mole of (S)-alpha-phenylethylamine to each mole of said acid in chloroform.
摘要:
Process for preparing esters of 2-(6'-methoxy-2'-naphtyl)-propionic acid via rearrangement of new ketals of 2-halo-1-(6'-methoxy-2'-naphtyl)-propan-1-one in the presence of a Lewis acid.The esters thus obtained are useful as intermediate products for preparing Naproxen.The process involves the preparation of the following new compounds:ketals of 2-halo-1-(6'-methoxy-2'-naphtyl)-propan-1-oneesters of 2-(5'-bromo-6'-methoxy-2'-naphtyl)-propionic acid1-(5'-bromo-6'-methoxy-2'-naphtyl)-propan-1-one2-halo-(5'-bromo-6'-methoxy-2'-naphtyl)-propan-1-one.
摘要:
A method of preparing ketoprofen by reacting aniline with a halide of an alpha-halogen propionic acid, benzylation of 3-methyl-2-indolinone, alkaline hydrolysis of 5-benzyl-3-methyl-2-indolinone, deamination of 2-(3-benzyl-6-aminophenyl)propionic acid and oxidation of 2-(3-benzylphenyl)propionic acid.
摘要:
Process for preparing Naproxen via a sequence of stereospecific reactions which comprises: condensation of 1-chloro-2-methoxy-naphthalene with a (S)-2-halo-propionyl halide according to the Friedel-Crafts reaction, ketalization of the thus obtained (S)-2-halo-1-(5'-chloro-6'-methoxy-2'-naphthyl)-propan-1-one, rearrangement of said ketal to afford an ester, hydrolysis of the ester and removal of the chlorine atom in 5-position by hydrogenolysis.New (S) 2-halo-1-(5'-chloro-6'-methoxy-2'-naphthyl)-propan-1-ones.
摘要:
Process for preparing alkanoic acid or their esters by rearrangement of alpha-halo-ketones in protic medium and in the presence of a non-noble metal salt.The protic medium is preferably an aliphatic alcohol having low molecular weight or water and the reaction is carried out at a temperature from 0.degree. C. to the boiling-point of the diluent or of the diluents mixture.