Picoline 3,5-dichloro

Photodecomposition products included acidic compounds and five methylated derivatives (Plimmer, 1970). When picloram in an aqueous solution (25 °C) was exposed by a high intensity monochromatic UV lamp, dechlorination occurred yielding 4-amino-3,5-dichloro-6-hydroxy-picolinic acid which underwent decarboxylation to give 4-amino-3,5-dichloropyridin-2-ol. In addition, decarboxylation of picloram yielded 2,3,5-trichloro-4-pyridylamine which may undergo dechlorination yielding 4-amino-3,5-dichloro-6-hydroxypicolinic acid (Burkhard and Guth, 1979). 

Pesticides. The compound 2-picoline is a component of l-[(4 -amino-2/- f-propyl-5 -pyrimidinyl )methyl]-2-picolinium chloride hydrochloride, known as Amprolium, a broad-spectrum coccidiostat. A newer coccidiostat is 3,5-dichloro-4-hvdToxy-2,6-lnfidine and known... 

The light-catalyzed chlorination of 2-picoline with chlorine water is said to involve substitution of the side-chain first, to give 2-trichloro-methylpyridine (11) which, under more vigorous conditions, gives the 5-chloro (12), the 3,5-dichloro (13), and the 3,4,5-trichloro, derivatives (14).40 The side-chain chlorination may well be a homolytic process,... 

Racemic baikiain can be obtained by an electrolytic reduction of picolinic acid60 (see Section II, B, 2), by an eight-step synthesis from l-benzoyloxy-4-bromo-2-butyne163 or, more simply, from cis-1,4-dichloro-2-butene (175).164... 

According to Kyriacou and coworkers [279], reduction of 3,4,5,6-tetrachloro-2-pico-linic acid at a silver electrode in an aqueous medium yields 3,4,6-trichloro-2-picolinic acid, which can be further reduced to 3,6-dichloro-2-picolinic acid. 

Several examples of direct chlorination of pyridines have appeared. The ferric chloride-catalyzed chlorination of 2-chloro-5-(trifluoromethyl)pyridine provides the 2,3-dichloro-5-(trifluoromethyl)pyridine (83EUP78410). Symmetrical tetrachloropyridine can be prepared by catalytic chlorination of 3-(trichloromethyl)pyridine (86EUP204848, 86JAP(K )61-277666). Chlorination of 6-hydroxy-2-picoline occurred at C-3 with >98% selectivity (86LJSP4594422). Vapor-phase catalytic chlorination of 2,6-dichloropyridine gives 2,3,5,6-tetrachloropyridine in good yield (83JAP(K)58-206564). 

Chlorination. Aliphatic aldehydes are converted to a,a-dichloro derivatives with chlorine using picoline hydrochloride as catalyst. On further reaction, the dichloro-carboxylic acids are formed. 

Moreover, the operation can also be accelerated by employing a catalyst (cuprous chloride) in solution in an organic solvent (such as a-picoline), and by raising the temperature. Above 160 0, however, large amounts of by-products are formed 1-chloro butadiene, hydrochloric acid and especially polymers. Thus, to prevent these side reactions it is preferable to maintain a low thermal level, 105 to 125°C, and distill under partial vacuum (about 20 kPa absolute), in the presence of an inhibitor intended to prevent polymerizations from developing (phenothiazine). For a once-through conversion of 1,4-dichloro 2-butenes of about 80 per cent, molar selectivity of the 3,4-isomer exceeds 75 per cen t. 

CAS 1702-17-6 57754-85-5 Synonyms 3,6-DCP 3,6-Dichloropicolinic acid 3,6-Dichloro-2-pyridinecarboxylic acid 3,6-Dichloropyridine-2-carboxylic acid Picolinic acid, 3,6-dichloro-... 

Picolinic acid, 3,6-dichloro-. See Clopyralid Picolinic acid ethyl ester. See Ethyl nicotinate P-Picolyl alcohol. See Pyridine-3-methanol PicoPure . See Hydrogen peroxide Picramic acid. See 2-Amino-4,6-dinitrophenol Picramic acid, sodium salt. See Sodium picramate... 

Photochlorination of 2-picoline (X-112) at 50 to 150° produces 3-chloro-2-trichloromethylpyridine (X-113) and 3,6-dichloro-2-trichloromethyl-pyridine (X-114). Hydrolysis with concentrated nitric acid gave a 95% yield of the corresponding 2-carboxylic acids. Continued photochlorination affords a perchlorinated trichloromethylpyridine (X-llS), which, after ammonolysis and boiling in sulfuric acid, afforded picloram (X-116). ... 

Poly [ (amino) phosphazenes] have been synthetised by the replacement of chlorine atoms in poly[(dichloro)phosphazene] by amines (Allcock et al, 1966). Drug molecules bearing an amino-group are substituted in the same way, such as the anesthetic molecules procaine, benzocaine, chloroprocaine, butyl-p-aminobenzoyl and 2-amino-4-picoline (Allcock et al, 1982). The poly [(diamino) phosphazene] is not water soluble but this can be achieved by cosubstitution with methylamine, procaine or 2-amino-4-picolino. 

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