| 摘要 |
<p>The subject matter of the invention is the process for the preparation of mixed ethers of formula I, wherein Ar represents an aromatic or one or more heteroatom-containing moiety, optionally substituted by one or more C1-4 alkoxy, methylenedioxy, C1-4 alkyl, halogen, C1-4 haloalkyl or nitro-group, and/or condensed with a benzene ring; R1 and R2 independently mean hydrogen, C1-4 alkyl, C1-4 haloalkyl, C2-4 alkenyl, phenyl, substituted phenyl, C3-6 cycloalkyl group, R3 means C3-6 alkynyl, optionally substituted by one or more C1-6 alkyl, C3-6 alkenyl, C3-6 alkynyl, C1-6 haloalkyl group, or halogen atom, R3 also means a C1-4 alkyloxy-C1-4 alkyloxy-C1-4 alkyl group. The process comprises the step of reacting the compounds of general formula II with 1 to 3 molar equivalent of the alcohol of general formula IlI in the presence of acid, a Lewis acid, a metal oxide or a metal carbonate, X means hydroxy, halogen or sulphonester leaving group, the resulting ether of general formula I is isolated, if desired, stabilized by the addition of a base and/or an antioxidant; and if desired the excess of the alcohol is recovered.</p> |
