Abstract: An inclusion compound comprising meta-cyclophane of the formula ##STR1## and at least one benzene derivative included therein. And a process for separating an isomer containing a substituent at least at the 1- and 4-positions from a mixture containing isomers of a benzene derivative, which comprises contacting the meta-cyclophane with the mixture containing isomers of a benzene derivative thereby to form an inclusion compound in which an isomer containing a substituent at least at the 1- and 4-positions is included in the meta-cyclophane, then separating the inclusion compound from the mixture, and thereafter separating the isomer from the inclusion compound.

Abstract: A process for preparing .beta.,.gamma.-unsaturated aldehydes which comprises dehydrogenating .beta.,.gamma.-unsaturated alcohols in the vapor phase, preferably in the substantial absence of oxygen, using copper having a specific surface area of 0.01 to 1.5 m.sup.2 /g as a catalyst at a temperature of 150.degree. to 300.degree. C. The .beta.,.gamma.-unsaturated aldehydes can be recovered in pure form by distilling the dehydrogenation reaction mixture in the presence of water. The starting .beta.,.gamma.-unsaturated alcohols can be prepared by reacting olefins with formaldehyde or a derivative capable of forming formaldehyde at a temperature of 180.degree. to 400.degree. C. in the absence of a solvent or in the presence of a non-aqueous organic solvent after pre-heating said formaldehyde or derivative to a temperature of 85.degree. to 150.degree. C.

Abstract: A process for recovering purified 4-hydroxy-2,4,6-trimethyl-2,5-cyclohexadiene-1-one by distilling crude 4-hydroxy-,2,4,6-trimethyl-2,5-cyclohexadien-1-one. Preferably, the distillation is performed at a temperature of 40.degree. to 250.degree.C. using crude 4-hydroxy-2,4,6-trimethyl-2,5-cyclohexadien-1-one having a pH of 4 to 11.5. Thus, 4-hydroxy-2,4,6-trimethyl-2,5-cyclohexadien-1-one of high purity and reduced coloration can be recovered at a high recovery ratio.

Abstract: A process for the preparation of 2,4,6-trimethylphenol by reacting a phenol of the formula (1) below, ##SPC1##In which R.sub.1 and R.sub.2 each stands for hydrogen atom or methyl groupWith methanol at vapor phase, in the presence of a magnesium oxide-containing catalyst, to methylate the former, the characteristic features residing in that the reaction is performed at the temperatures ranging from 400.degree. to 500.degree.C., and the gaseous mixture composed essentially of the phenol and methanol is contacted with the catalyst at a flow rate not higher than 0.4/hour (sum weight in grams of the phenol and methanol/catalyst's weight in grams/hour).

Abstract: A process for preparing 4-hydroxy-2,4,6-trimethyl-2,5-cyclohexadiene-1-one comprising reacting 2,4,6-trimethyl phenol with molecular oxygen or a molecular oxygen-containing gas. The product (also called mesitylquinol) is an intermediate useful as a raw material for the synthesis of a variety of industrial chemicals such as a drugs, dyestuffs, and pigments.

Abstract: This invention is directed to a process for preparing trimethylhydroquinone (TMHQ) by heating 4-hydroxy-2,4,6-trimethyl-2,5-cyclohexadiene-1-one (HTCD) in a nonacidic liquid medium consisting of either methanol or an aqueous medium, preferably in the presence of a basic substance, at a temperature of at least 100.degree.C., and preferably 150.degree.-300.degree.C.Thus, according to this invention, TMHQ of high purity and small coloration can be prepared from HTCD in good yield, for example, as high as 85 - 98%.