3.4- dimethyl-1,1,1 -trichloro

Reactions of Phosphoranes.—Dimethyl(trichloro)phosphorane (94) reacts with 1-acetylsemicarbazides to form the bicyclic phosphoranes (95). . Y-Ray analysis of the bicyclo[3,2,0]heptane derivative reveals a distorted tbp structure for (95). 

Ci9Hi7N5S2Sn, Dimethyldiisothiocyanato(terpyridyl)tindV), 39B, 548 Cl9H23Cl4N3Sn2, 2,2 ,2 -Terpyridyl(dimethyl)chlorotin IV) dimethyl-(trichloro)stannate(lV), 33B, 314... 

Successful results have been obtained (Renfrew and Chaney, 1946) with ethyl formate methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec.-butyl and iso-amyl acetat ethyleneglycol diacetate ethyl monochloro- and trichloro-acetates methyl, n-propyl, n-octyl and n-dodecyl propionates ethyl butyrate n-butyl and n-amyl valerates ethyl laurate ethyl lactate ethyl acetoacetate diethyl carbonate dimethyl and diethyl oxalates diethyl malonate diethyl adipate di-n-butyl tartrate ethyl phenylacetate methyl and ethyl benzoates methyl and ethyl salicylates diethyl and di-n-butyl phthalates. The method fails for vinyl acetate, ieri.-butyl acetate, n-octadecyl propionate, ethyl and >i-butyl stearate, phenyl, benzyl- and guaicol-acetate, methyl and ethyl cinnamate, diethyl sulphate and ethyl p-aminobenzoate. 

Cyclization. Constmction of ben2otrifluorides from aHphatic feedstocks represents a new technique with economic potential. For example, l,l,l-trichloro-2,2,2-trifluoroethane [354-58-5] and dimethyl itaconate [617-52-7] form 4-methoxy-6-trifluoromethyl-2JT-pyran-2-one [101640-70-4] which is converted to methyl 3-(trifluoromethyi)ben2oate [2557-13-3] ixh. acetjdene or norbomadiene (125). 

In some instances a carbon-carbon bond can be formed with C-nucleophiles. For example, 3-carboxamido-6-methylpyridazine is produced from 3-iodo-6-methylpyridazine by treatment with potassium cyanide in aqueous ethanol and l,3-dimethyl-6-oxo-l,6-dihydro-pyridazine-4-carboxylic acid from 4-chloro-l,3-dimethylpyridazin-6-(lH)-one by reaction with a mixture of cuprous chloride and potassium cyanide. Chloro-substituted pyridazines react with Grignard reagents. For example, 3,4,6-trichloropyridazine reacts with f-butyl-magnesium chloride to give 4-t-butyl-3,5,6-trichloro-l,4-dihydropyridazine (120) and 4,5-di-t-butyl-3,6-dichloro-l,4-dihydropyridazine (121) and both are converted into 4-t-butyl-3,6-dichloropyridazine (122 Scheme 38). 

An acid-catalyzed substitution of a 6-oxo group on 2-aminopteridine-4,6-dione with hydrogen chloride in alcohols (65-100°, 3 hr, 80% yield) represents a convenient synthesis of the 6-alkoxy analogs. The reaction proceeds also with pteridine-2,4,6-trione and its 1-methyl and 1,3-dimethyl derivatives. While methoxylation of 2,4,7-trichloro-quinoline gives about equal amounts of 2- and 4-substitution, acid-catalyzed hydrolysis gives specific reaction at the 2-position only. ... 

A. N-Trijluoroacetanilide. In a two-necked, round-bottomed flask fitted with a thermometer, a Drierite tube, and a magnetic stirring bar are placed 4.56 ml. (4.66 g., 0.050 mole) of aniline [Benzenamine] (Note 1) and 15 ml. of dimethyl sulfoxide (Note 2). The resulting solution is stirred and cooled in an ice water bath, and when the internal temperature has dropped to 10-15°, 21.5 g. (0.10 mole) of 1,1,1-tri-chloro -3,3,3 -trifiuoroacetone [2 -Propanone, 1,1,1 -trichloro-3,3,3-tri-fluoro-] (Note 3) is added in portions through the condenser. A mild exotherm results, and the addition is extended over ca. 5 minutes to... 

Dimethyl-2,3(l, 4//)-quinoxalinedione gave 2,3-dichloro-6,7-dimethylqui-noxaline (13) (POCI3, PhNMe2, reflux, A, 8h 94%) 6-chloro-7-nitro-2,3(1//,4//)-quinoxalmedione gave 2,3,6-trichloro-7-nitroquinoxaline (14) (POCI3, PhNMc2, reflux, 90 min 75%). ... 

A new type of asymmetric hydrosilylation which produces axially chiral allenylsilanes has been reported by use of a palladium catalyst coordinated with the bisPPFOMe ligand 51b.64 The hydrosilylation of l-buten-3-ynes substituted with bulky groups such as tert-butyl at the acetylene terminus took place in a 1,4-fashion to give allenyl(trichloro)-silanes with high selectivity. The highest enantioselectivity (90% ee) was observed in the reaction of 5,5-dimethyl-T hexen-3-yne with trichlorosilane catalyzed by the bisPPFOMe-palladium complex (Scheme 13). 

Phosphorothioic acid, 0,0-dimethyl 0-(2,4,5-trichloro-phenyl) ester, see Ronnel... 

Plant. Fewer and Owen (1989) found 3,5,6-trichloro-2-pyridinol as the major metabolite in plants. Cultured soybean cells metabolized triclopyr to dimethyl triclopyr-aspartate and dimethyl triclopyrglutamate which can be rehydrolyzed to form the parent compound. 

Meikle, R.W. and Youngson, C.R. The hydrolysis rate of chlorpyrifos, 0,0-diethyl 0-(3,5,6-trichloro-2-pyridyl) phosphoro-thioate, and its dimethyl analog, chloropyrifos-methyl in dilute aqueous solution, Arch. Environ. Contam. Toxicol,... 

Other electrochemical processes of organic compounds on Pb electrodes or electrodes with UPD Pb have been studied - formaldehyde [323], oxalic acid [386], trichloro- and trifluoroethane [387], 1-phenylethylamine [388], 3-hydroxychi-nuclidine [388], dichlorodifluoromethane [389], polychlorobenzenes [390], 1-propa-nol [391], pyrrole polymerization [392], and inorganic compounds - phosphine [388] and sulfate(IV) ions [393]. Simultaneous catalytic or inhibiting influence of organic solvents - acetonitrile, dimethyl-sulfoxide, and Pb + presence on electrooxidation of small organic molecules on Pt electrodes has been studied using on-line mass spectroscopy [394],... 

B. TRIS(DIMETHYL SULFOXIDE)INDIUM(IIl) CHLORIDE [TRICHLORO-TRIS(DIMETHYL SULFOXIDE)INDIUM(III)]... 

The configuration of ethyl (S)-4,4,4-trichloro-3-hydroxybutanoate, (8), obtained from ethyl 4,4,4-trichloro-3-oxobutanoale by yeast reduction (see p 403), was assigned by conversion to (—)-dimethyl 2-hydroxybutanedioate (9)78 by treatment with hydroxide in a process which occurs with inversion of configuration207. 

In a closely related investigation, designed to generate vinyl alcohol in solution, divinyl hemiorthoformate [68] was detected as an intermediate in the hydrolyses of divinyloxymethyl dichloro- and trichloro-acetate [67] (Capon et al., 1981b). It is interesting that methyl vinyl hemiorthoformate could not be detected in the hydrolysis of methoxyvinyloxymethyl acetate and chloroacetate under similar conditions. So dimethyl and divinyl hemiorthoformate appear to be more stable than methyl vinyl hemiorthoformate. 

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