Abstract: This invention reveals a process for the synthesis of 2-methylbutanal (2-methylbutyraldehyde). 2-methylbutanal is a chemical intermediate that is useful in the synthesis of isoprene (2-methyl-1,3-butadiene). In utilizing the process of this invention 2-butene is hydroformylated into 2-methylbutanal with only a minimal amount of n-pentanal being produced as a by-product. More specifically, this invention reveals a process for the synthesis of 2-methylbutanal from 2-butene comprising: hydroformylating 2-butene with a catalyst selected from the group consisting of hydridocarbonyltris (triphenylphosphine) cobalt, hydridocarbonyltris (triphenylphosphine) rhodium, and hydridocarbonyltris (triphenylphosphine) iridium in the presence of hydrogen and carbon monoxide wherein said hydroformylation is carried out in the presence of excess triphenylphosphine.

Abstract: There is disclosed a process for the preparation of cyclopentene which comprises selectively hydrogenating cyclopentadiene in a liquid phase by contacting cyclopentadiene with hydrogen in the presence of a hydrogenation catalyst comprising (1) a soluble nickel compound, (2) an organoaluminum compound or a lithium alkyl compound, and (3) at least one cocatalyst compound selected from the group consisting of H.sub.2 O; NH.sub.3 ; ROH where R is an alkyl or a halogenated alkyl radical containing from 1 to 20 carbon atoms; ##STR1## where R.sub.1, R.sub.2 and R.sub.3 may be hydrogen, or an alkyl radical containing from 1 to 6 carbon atoms; ##STR2## where R.sub.1, R.sub.2 and R.sub.3 may be hydrogen or halogen, or an alkyl radical containing from 1 to 6 carbon atoms; R.sub.1 O R.sub.2 wherein R.sub.1 and R.sub.2 may be the same or different alkyl radicals containing from 1 to 6 carbon atoms; and ##STR3## wherein R.sub.1 may be alkyl or an aromatic radical containing from 1 to 8 carbon atoms and R.sub.

Abstract: There is disclosed an improved process for selectively hydrogenating cyclopentadiene to form cyclopentene in the presence of a catalyst comprising (A) a hydrocarbon-soluble nickel compound such as nickel salts of carboxylic acids or organo nickel compounds, (B) an organo reducing agent such as organoaluminum compounds or lithium alkyl compounds and (C) pyridine, the improvement being that the soluble nickel compound and the pyridine are employed in amounts wherein the mole ratio of aluminum or lithium to the nickel ranges from 7/1 to 11/1 and the mole ratio of the pyridine to the nickel compound ranges from 1/1 to 2.5/1.

Abstract: There is disclosed an olefin metathesis process which comprises subjecting at least one olefin to a catalyst system consisting of (1) salts of the metals selected from the group of tungsten, molybdenum and chromium, said salts being halides or the reaction products of these metal halides with carboxylic acids, phenols and 1,3-diketones, (2) a material selected from the group represented by the formulae:R.sub.3-n MX.sub.nandR.sub.3 M.sub.2 X.sub.3wherein R is an alkyl radical containing from 1 to 12 carbon atoms, M is selected from the group consisting of aluminum, gallium and indium, X is a halogen from the group of fluorine, chlorine, bromine and iodine, and n equals 0, 1 or 2, and (3) a compound defined by the formula:N R.sub.1 R.sub.2 R.sub.3in which R.sub.1 and R.sub.2 are selected from the group of hydrogen, alkyl, aralkyl, aryl, alkenyl and alkaryl, R.sub.

Abstract: There is disclosed a method for isomerizing cyclic olefinic hydrocarbons to bicyclic olefins by contacting the cyclic olefins with a catalyst comprised of at least (1) a nickel compound selected from the class consisting of nickel salts of carboxylic acids and organonickel complexes and (2) at least one co-catalyst consisting of organoaluminum compounds or aluminum trihalides at atmospheric pressure and ambient temperatures.

Abstract: There is disclosed a method of selective hydrogenation of cyclopentadiene which comprises contacting cyclopentadiene with hydrogen in the presence of a catalyst comprising aluminum trialkyl and organonickel compounds. The preferred solvent system for the hydrogenation process is an aliphatic alcohol.