Abstract: Novel 2-methylene-3-methyl-3-(1',3'-pentadien-1'-yl)-bicyclo-[2,2,1]-heptanes substituted in the 4'-position by methyl, alkoxycarbonyl, formyl, hydroxymethyl or cyano are obtained by reacting the novel aldehyde 2-methylene-3-methyl-3-formyl-bicyclo-[2,2,1]-heptane with 3-methyl-, 3-alkoxycarbonyl- or acetalized 3-formyl-2-butene-1-triarylphosphorylidene under the conditions of a Wittig reaction, with or without hydrolytic cleavage of the acetal group, or hydrolytic cleavage of the acetal group followed by reduction of the formyl group to the hydroxymethyl group, or hydrolytic cleavage of the acetal group, reaction of the aldehyde with a hydroxylammonium salt, and dehydration of the resulting oxime.The novel compounds are distinguished by interesting scent characteristics.

Abstract: An improved process for the catalytic dehydration of alcohols to form unsaturated organic compounds is provided in which an alcohol is dehydrated in the presence of alumina catalysts which are pre-treated with an organic silylating agent at elevated temperature.

Abstract: Acyclic terpenoid onium salts are cyclized in an acidic aqueous solution at a temperature of at least about 80.degree. C.

Abstract: Olefinically unsaturated aliphatic or cycloaliphatic hydrocarbons are manufactured by bringing alkanecarboxylic acids of 3 to 20 carbon atoms, alkanedicarboxylic acids of 4 to 20 carbon atoms or 5-membered or 6-membered cycloalkanecarboxylic acids or their alkyl, cycloalkyl, aralkyl or phenyl esters, in the gas phase, at from 250.degree. to 800.degree. C., into contact with catalysts in which the active composition consists of boron trioxide, boric acid and/or boron nitride, together with one or more of the oxides of aluminum, silicon, tin, lead, titanium and zirconium.

Abstract: A process for cleavage of unsaturated multi-cyclic ketones involves thermal cracking of the liquid ketone at elevated temperatures in the absence of water to produce cyclohexanone and a variety of other cleavage products. Para-toluenesulfonic acid and transition metal oxides are advantageously employed as catalysts.