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:
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:
3-Isochromanome is prepared by reacting an o-xylene-&agr;,&agr;′-dihalide with carbon monoxide and water in the presence of a metal catalyst such that the pH of the reaction is maintained between about 7 and 11.
摘要:
A process for the preparation of 2-hydroxy-6-trifluoromethylpyridine which comprises reacting 2-fluoro-6-trifluomethylpyridine or a mixture of 2-fluoro-6-trifluoromethylpyridine and 2-chloro-6-trifluoromethylpyridine with an alkali metal hydroxide at a temperature of from 50.degree. C. to 160.degree. C. and acidifying the product so formed.
摘要:
A process for extracting from aqueous solution the alkali metal or ammonium salt of a phenol, naphthol, anthrol or phenanthrol or the corresponding thiol, which comprises contacting an aqueous alkaline or neutral solution of the alkali metal or ammonium salt, in which is dissolved an alkali metal or ammonium fluoride, chloride, bromide, hydroxide, nitrate, nitrite, sulphate, sulphite, sulphide, thiosulphate, phosphate, hydrogen phosphate, carbonate, bicarbonate, cyanate, cyanide, thiocyanate, borate, chlorate, chlorite, hypochlorite, perchlorate, chromate, dichromate or permanganate, with a partially water-miscible organic solvent so as to transfer aqueous solution of the alkali metal or ammonium salt of the phenol, naphthol, anthrol or phenanthrol or corresponding thiol into the solvent while retaining separate aqueous and solvent phases, and thereafter separating the solvent phase containing the alkali metal or ammonium salt and water from the aqueous phase, the ratio of solvent to water in the separated solvent phase being from 0.5:1 to 10:1 w/w.
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:
4,6-Dichloropyrimidine is prepared by treating 4,6-dihydroxypyrimidine with a chlorinating agent of the formula R.sup.1 R.sup.2 R.sup.3 PCl.sub.2 wherein R.sup.1, R.sup.2 and R.sup.3 are independently alkyl or aryl, or one or more of the groups R.sup.1, R.sup.2 and R.sup.3 is linked to a polymer support. Conveniently, the chlorinating agent may be prepared in situ by reacting the corresponding phosphine oxide with phosgene. Thus, in a preferred process, 4,6-dichloropyrimidine is prepared by treating 4,6-dihydroxypyrimidine with phosgene in the presence of a phosphine oxide.
摘要翻译:通过用式R 1 R 2 R 3 PCl 2的氯化剂处理4,6-二羟基嘧啶来制备4,6-二氯嘧啶,其中R 1,R 2和R 3独立地是烷基或芳基,或者R 1,R 2和R 3中的一个或多个与 聚合物支持。 方便地,氯化剂可以通过使相应的氧化膦与光气反应而原位制备。 因此,在优选的方法中,通过在氧化膦存在下用光气处理4,6-二羟基嘧啶来制备4,6-二氯嘧啶。
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:
2-Hydroxy-6-trifluoromethylpyridine is prepared by reacting 2-chloro-6-trifluoromethylpyridine with an aqueous alkali metal hydroxide in a sealed vessel at a temperature of at least 140.degree. C. under autogenous pressure.
摘要:
A process for preparing agrochemical intermediates of formula (I), wherein W is (CH.sub.3 O).sub.2 CH.CHCO.sub.2 CH.sub.3 or CH.sub.3 O.CH.dbd.CCO.sub.2 CH.sub.3 ; Z.sup.1 is a halogen atom; and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently hydrogen, halogen, C.sub.1-4 alky, C alkoxy, acetoxy or acyl; the process comprising the steps of: (a) reacting a compound of formula (II), wherein X, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are as defined above, with a compound of formula ROCH.sub.3, wherein R is a metal; and, (b) reacting the product of (a) with a compound of formula (III), wherein Z.sup.1 and Z.sup.2 are halogen atoms. A process for the preparation of compounds of formula (II) and compounds of formula (II) themselves. A process for obtaining, in substantially pure form, a compound of formula (11) and compounds of formula (II) themselves. A process for obtaining, in substantially pure form, a compound of formula (11) wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are all hydrogen.