摘要:
3-Isochromanone is prepared by partially chlorinating o-tolylacetic acid with sulphuryl chloride or chlorine gas in an inert organic solvent in the presence of a free radical initiator. The 2-chloromethylphenylacetic acid first obtained is converted to 3-isochromanone by treatment with a base and separated from unreacted o-tolylacetic acid, which is in the form of a salt, by a phase separation technique. The separated o-tolylacetic acid salt is converted to o-tolylacetic acid by controlled acidification and the o-tolylacetic acid is extracted for re-use. The invention reduces the formation of unwanted, over-chlorinated by-products and leads to a more efficient process.
摘要:
A process for the preparation of 3-isochromanone which comprises contacting an o-xylene-α,α′-dihalide with carbon monoxide, in the presence of a catalyst and a hindered amine base in a liquid medium comprising water and a tertiary alcohol.
摘要:
A process for preparing 4,6-dichloropyrimidine is described, comprising treating 4,6-dihydroxypyrimidine with phosphorus oxychloride in the presence of a saturated hindered amine, the hydrochloride salt of a saturated hindered amine, or an unsaturated 5-membered nitrogen containing ring or a mixture thereof, and, as a first step, directly extracting the 4,6-dichloropyrimidine so formed.
摘要:
3-Isochromanone is prepared by contacting an o-xylene-&agr;,&agr;′-dihalide with carbon monoxide in a two-phase liquid medium, in which one phase is aqueous and the other phase is water-immiscible, in the presence of a catalyst and a hindered amine base.
摘要:
A process for preparing 4,6-dihydroxypyrimidine comprising the steps:a) contacting formamide, an alkoxide of formula ROM and a malonate of formula CH.sub.2 (CO.sub.2 R).sub.2 in a solvent of formula ROH;b) adding water to the product of step (a);c) removing substantially all of the solvent of formula ROH from the product of step (b); andd) acidifying the product of step (c)wherein R is C.sub.1-4 alkyl and M is an alkali metal.
摘要:
Methyl 2-(chloro- or bromomethyl)phenylacetate is prepared by treating 3-isochromanone with thionyl chloride or thionyl bromide in the presence of methanol.
摘要:
A process for preparing 2-(6-substituted pyrid-2-yloxymethyl)phenyacetates especially useful as intermediates for producing agricultural fungicides. The invention provides a compound having the formula (I): wherein A and D are independently selected from the group comprising halo, hydroxy, halo(C.sub.1-4)alkyl, C.sub.1-4 alkoxy, thio(C.sub.1-4)alkoxy, halo(C.sub.1-4)alkoxy, phenyl, phenoxy, nitro, amino, aclyamino, cyano, carboxy, C.sub.1-4 alkoxycarbonyl and C.sub.1-4 alkylcarbonyloxy, or D is C.sub.1-4 alkyl, and m is 0 or an integer of from 1 to 3. The process comprises treating a compound of formula (II): ##STR1## wherein A, D and m are defined as above and M is a metal atom, with a compound of formula (III): ##STR2## wherein L is a leaving group.