Abstract: The present invention relates to a process for the preparation of 2-(benzhydrylthio)acetamide (II), key intermediate for the synthesis of modafinil, by reaction of benzhydryl chloride with thiourea and chloroacetamide.

Abstract: A process for the preparation of sodium divalproate by reacting valproic acid and sodium methoxide in an inert solvent, azeotropically removing the formed methanol.

Abstract: A process for the preparation of gabapentin of formula (I) which comprises: a) reduction of (1-nitromethyl-cyclohexyl)acetonitrile of formula (II)  to give 3-imino-2-aza-spiro[4.5]decan-2-ol of formula (III) b) transformation of compound (III), by alkali treatment, into 2-hydroxy-2-aza-spiro[4.5]decan-3-one of formula (IV) c) reduction of compound (IV) to give 2-aza-spiro[4.5]decan-3-one of formula (V) d) hydrolysis of compound (V) to gabapentin.

Abstract: A process for the production and purification of gabapentin, i.e. 1-(aminomethyl)cyclohexyl-acetic acid, which comprises hydrolysis of 2-aza-spiro[4.5]decan-3-one with HCl, treatment of the resulting product and filtration with acetone, dissolution in water at isoelectric pH and crystallization or digestion in the hot in mixtures of diisopropyl ether with ethanol or methanol.

Abstract: A process for the preparation of sodium divalproate by reacting valproic acid and sodium methoxide in an inert solvent, azeotropically removing the formed methanol.

Abstract: A process for the preparation of gabapentin of formula (I) 1

Abstract: The invention relates to a method for preparing HMP terfenadine comprising the steps of reacting terfenadone free-base with sodium borohydride to yield mixed polymorph terfenadine and crystallizing said mixed polymorph terfenadine from a seeded ester or ketone solvent system to yield substantially pure HMP terfenadine.

Abstract: A novel process for the preparation of alkyl isocyanates comprising reacting COX.sub.2 and an alkyl amine hydrohalide of the formulaR-NH.sub.2.HX Iwherein R is alkyl of 1 to 3 carbon atoms and X is a halogen either under pressure in an inert organic solvent or under atmospheric pressure in a high boiling organic solvent to form the corresponding alkyl carbamoyl halide, reacting the latter in an organic solvent with an urea of the formula ##STR1## wherein X' is selected from the group consisting of oxygen and sulfur, R.sub.1 and R.sub.3 are individually selected from the group consisting of alkyl of 1 to 7 carbon atoms, cycloalkyl of 4 to 6 carbon atoms and phenyl and R.sub.2 and R.sub.4 are individually selected from the group consisting of hydrogen, alkyl of 1 to 7 carbon atoms, cycyloalkyl of 4 to 6 carbon atoms and phenyl to obtain the corresponding alkyl isocyanate.