Abstract: A catalytic hydrogenation process for converting maleic anhydride and/or succinic anhydride to gamma-butyrolactone, a novel selective catalyst for use in such process and a method of preparing the catalyst are provided. The process comprises contacting maleic anhydride and/or succinic anhydride with hydrogen in the presence of catalysts whereby the anhydride is converted to predominantly gamma-butyrolactone. The catalyst of the invention is comprised of transition metals, their oxides and mixtures thereof on a silica gel support having a high surface area and pore volume.

Abstract: A process for recycling the difluoro sugar in the synthesis of 2,2-difluoronucleosides proceeds by removing the base moiety of .alpha.-difluoronucleosides by reduction and hydrolysis, followed by oxidation to put the difluro sugar in a form conventiently recycled into the synthesis, and intermediates useful therefor.

Abstract: A process is described for the production of substantially pure gamma-butyrolactone from a feed mixture containing a major amount of gamma-butyrolactone and a minor amount of diethyl succinate which comprises fractionally distilling the mixture in a fractionation zone in the presence of diethyl ethoxysuccinate and recovering from the fractionation zone an overhead vaporous product comprising gamma-butyrolactone which is substantially free from diethyl succinate and is liquid bottom product comprising diethyl ethoxysuccinate and diethyl succinate in admixture one with another. This procedure can be used to separate a gamma-butyrolactone rich fraction obtained by distillation in one or more stages of a crude reaction product obtained by hydrogenation of a C.sub.

Abstract: A method for producing a lactone by hydrogenating a dicarboxylic acid, a dicarboxylic acid anhydride and/or a dicarboxylic acid ester in the presence of a catalyst, wherein the hydrogenation reaction is conducted in the liquid phase in the presence of (1) ruthenium, (2) an organic phosphine and (3) a compound of a metal selected from the group consisting of Groups IVA, VA and IIIB in the Periodic Table.According to the present invention, for the production of a lactone by hydrogenating a dicarboxylic acid, a dicarboxylic acid anhydride and/or a dicarboxylic ester, the reaction is conducted in a homogeneous liquid phase reaction by using the ruthenium, organic phosphine and compound of a metal selected from the group consisting of Groups IVA, VA and IIIB, of the present invention as the catalyst, whereby the desired lactone product can be obtained at high selectivity under a mild condition as compared with the conventional methods.

Abstract: A method for producing a lactone by hydrogenating a dicarboxylic acid, a dicarboxylic acid anhydride and/or a dicarboxylic acid ester in the presence of a catalyst, wherein said catalyst is a ruthenium catalyst comprising (1) ruthenium, (2) an organic phosphine and (3) a conjugate base of an acid having a pKa of less than 2.

Abstract: A process is disclosed for preparing butyrolactones, butanediols, and mixtures thereof comprising hydrogenating a hydrogenatable precursor in the presence of an aqueous reaction medium and a catalyst comprising palladium or combinations thereof with rhenium and at least one support selected from the oxides of titanium, zirconium, and hafnium.

Abstract: A process for preparing primarily gamma-butyrolactone comprises the step of contacting under suitable reaction conditions a succinic anhydride containing feed stream and hydrogen, in the presence of a catalyst composition comprising (a) substantially metallic nickel, (b) at least one oxide selected from oxides of cerium and zirconium, and (c) a silica-containing support. In another embodiment, the above described catalyst composition is provided.

Abstract: A process for preparing primarily gamma-butyrolactone comprises the step of contacting under suitable reaction conditions a succinic anhydride containing feed stream with hydrogen gas, in the presence of a catalyst comprising metallic nickel and an aluminum phosphate containing support.

Abstract: A process for preparing primarily gamma-butyrolactone comprises the step of contacting under suitable reaction conditions a succinic anhydride containing feed stream and hydrogen, in the presence of a catalyst composition comprising (a) substantially metallic nickel, (b) at least one oxide selected from oxides of cerium and zirconium, and (c) a silica-containing support. In another embodiment, the above described catalyst composition is provided.

Abstract: The rate of selective hydrogenation of carboxylic acid anhydrides to esters or lactones in the presence of a ruthenium organophosphorous catalyst which contains or liberates a hydrogen halide during the hydrogenation, is improved by providing in the reaction medium prior to or during the hydrogenation a basic amino compound to remove the hydrogen halide.

Abstract: Process for selective homogeneous catalytic hydrogenation of carboxylic acid anhydrides to ester or lactones at an improved rate and to obtain improved yields wherein the catalyst is a ruthenium trichlorostannate complex of the formula: ##STR1## wherein X is hydrogen, chlorine, bromine, iodine or lower alkyl; m is the integer 1 or 2; n is an integer of from 0 to 3 but when n is 2 or 3, X may be the same or different; M is P, As or Sb; R.sup.6, R.sup.7 and R.sup.8 independently are lower alkyl, cycloalkyl, aryl, benzyl or a bidentate legand; x is an integer of from 1 to 4 but when x is 2 or more, M may be the same or different; L is a neutral ligand, olefin, CO or (R.sup.9).sub.2 CO wherein R.sup.9 is lower alkyl; y is an integer of from 0 to 3 but when y is 2 or 3, L may be the same or different; and the sum of x and y is at least 2.

Abstract: Compounds of the formula ##STR1## wherein R.sub.1 is hydrogen; trifluoromethyl; alkyl of 1 to 11 carbon atoms; cycloalkyl of 3 to 7 carbon atoms; hydroxyl; alkoxy of 1 to 6 carbon atoms; mercapto; (alkyl of 1 to 6 carbon atoms)-mercapto; phenyl-(alkyl of 1 to 3 carbon atoms); phenyl; or mono-, di- or tri-substituted phenyl, where the substituents, which may be identical to or different from each other, are each halogen, alkyl of 1 to 4 carbon atoms, (alkyl of 1 to 6 carbon atoms)-sulfinyl, hydroxyl, alkoxy of 1 to 6 carbon atoms, mercapto or (alkyl of 1 to 6 carbon atoms)-mercapto;R.sub.2 is hydrogen, alkyl of 1 to 6 carbon atoms, cycloalkyl of 3 to 6 carbon atoms or phenyl-(alkyl of 1 to 3 carbon atoms); andR.sub.3 is alkyl of 1 to 6 carbon atoms; optically active antipodes thereof; and non-toxic, pharmaceutically acceptable acid addition salts of said compounds or of said optically active antiposed. The compounds are useful as cardiotonics and antithrombotics.