A process for preparing 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran in which 2-methallyloxyphenol is heated to a temperature in the range of 150.degree. C. to 250.degree. C. in the presence of a solvent and a Lewis acid catalyst under an autogenous pressure of 20 to 60 psig is disclosed and exemplified.
A process for the isolation of a dihydroxybenzenemonoether from a reaction mixture containing solvent, ether and unreacted dihydroxybenzene, comprising contacting the reaction mixture with at least one hydrocarbon which is not miscible or only partially miscible with the reaction mixture, the ether selectively entering the hydrocarbon. Advantageously the reaction for the preparation of the monoether is carried out in an alcohol, a ketone, a dipolar aprotic solvent or a polyhydroxyalkyl ether, or a mixture thereof with water, the hydrocarbon used as extracting agent has a boiling point between about 80.degree. and 300.degree. C., and the extraction is carried out in the presence of water whereby there is an increase in the selectivity of the extraction.
A process for preparing 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran which comprises subjecting o-methallyloxyphenol to a rearrangement and cyclization reactions in the presence of, as a catalyst, aluminum halide and N-substituted aniline derivative, or a complex of both these compounds.
A process for the production of benzofuran derivatives having the general formula, ##STR1## wherein R is alkyl, in particular of 2,3-dihydro-2,2-dimethyl benzofuran-7-ol, starting from pyrocatechol ethers in one step operation. The process essentially consists of heating a solution of pyrocatechol ether in an inert organic solvent in the presence of a catalyst comprising metals of 3.degree. and 4.degree. group of the Periodic System in form of carboxylates or of modified zeolites. The products are known intermediates for the production of insecticides.
2,3-Dihydro-2,2-dimethyl-7-hydroxybenzofuran is prepared by reacting catechol with isobutylene oxide or with a compound having the general formula ##STR1## wherein R is halogen or hydroxyl, and X is halogen, in the presence of a base to form the intermediate 2-(2-hydroxy-2-methylpropoxy) phenol and then thermally dehydrating, rearranging and cyclizing the resulting intermediate phenol in the presence of an acid catalyst to form 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran.
