Abstract:
PROBLEM TO BE SOLVED: To obtain a new compound useful as a raw material for a new compound utilizing a naphthalene skeleton, a raw material for a monomer for a polyether, a polysulfide and a polythioester, and the like. SOLUTION: This new compound is represented by formula I (X is oxygen or sulfur; R is an alkyl, an aryl, an aralkyl or the like; Z is H, a halogen, an alkyl or the like), and exemplified by 6,7-bis[(methoxy)methyl]-2-oxa-2,3- dihydrophenalene. The compound of formula I is obtained by reacting a compound of formula II (Y is a halogen), [e.g. 1,4,5,8-tetrakis(bromomethyl) naphthalene] with a metal alkoxide such as sodium methoxide, or a metal thioalkoxide such as sodium methylthiomercaptide in an organic solvent such as methanol, preferably at a temperature from room temperature to about 100 deg.C, usually for 10-30 hr.
Abstract:
PURPOSE:To provide a method for reducing the amount of a Lewis acid to be used for solving problems such as the generation of a corrosive acidic gas in a Friedel-Crafts reaction industrially using a large amount of the Lewis acid. CONSTITUTION:When an aromatic compound is acylated with an acid halide or acid anhydride by their Friedel Crafts reaction, the Lewis acid and a catalytic amount of a silver salt are simultaneously used to reduce the amount of the Lewis acid to be used.
Abstract:
NEW MATERIAL:A compound expressed by formula I [ring A is (substituted) benzene ring; R is H or (substituted)hydrocarbon; B is (esterified or amidated) carboxyl; X is CH(OH) or CO; (k) is 0 or 1; (k') is 0-2]. EXAMPLE:6-Chloro-3,4-dihydro-1H-2-benzothiopyran-4'-one-1-carboxylic acid. USE:Useful as preventive and therapeutic agent for osteoporosis by bone adsorption suppressing action thereof. PREPARATION:A compound expressed by formula II (B' is esterified carboxyl; Y is OH or halogen) or salt thereof is subjected to ring-closing reaction and then, as necessary, subjected to oxidation reaction or/and hydrolysis reaction, or hydrolysis reaction followed by amidation reaction, or hydrolysis reaction followed by amidation reaction and oxidation reaction.