3-Chloro-trans-cinnamic acid

Chloro-trans-cinnamic acid, 38B, 158 p-Chloro-trans-cinnamic acid, 41B, 12... 

The reaction has also been applied to the conversion of vinyl bromides into acrylic acids, e.g. 1-bromo- and 1-chlorocyclooctene are converted into cyclooctene-1-carboxylic acid (ca. 98%) [3], 2-chloro-3,3-dimethylbut-l-ene yields 4,4-dimethylpent-2-enoic acid (95%), and tams-cinnamic acid is obtained (85%) from fran.v-p-bromostyrene. cis-p-Bromostyrene produces a mixture of cis- and trans-cinnamic acids in 38 and 42% yields, respectively [3]. In these reactions, benzyltri-ethylammonium chloride cannot be used as the phase-transfer catalyst, as it leads to the production of phenylacetic acid [3]. 

C9H802 trans-cinnamic acid 140-10-3 573.15 50.955 1,2 16292 C9H9CIO 2-chloro-1-(4-methylphenyl)ethanone 4209-24-9 534.65 47.223 1.2... 

Photosensitized crosslinking of polymers has been the subject of numerous publications [l - 30], concerned mainly with poly(ethylene), poly(vinyl alcohol), various vinyl copolymers, copolymers of maleic anhydride and/or phtalic anhydride with styrene and some polymers derivated from cinnamic acid. The following compounds were used as sensitizers benzophenone, 4-chloro- and 4,4-dimethylbenzophenone [l, 3-6, 8, 9l, oC -and -derivatives of anthraquinone [3, 23] acetophenone, hydroquinone, triphenylmethane and pyridine li.] chlorobenzene and no less than trichlorinated n-paraffins [6], a complex of zink chloride with o-dia-nizidine fill potassium bichromate [l2j, anthracene fl3, 14] 2,5-methoxy-4-amino-trans-stilbene [l5], benzyl ideneacetophenone fl6-l8] -thiophenylacetophenone,... 

The versatility of TOT in clathrate formation is further illustrated by the discovery of several other clathrate types belonging to various space groups PT (/raw-stilbene, cw-stilbene a-bromobutyric acid benzene ) Pl(PT) (methyl tran -cinnamate, methyl cw-cinnamate) P2 (weso-2,3-butanediol carbonate) P2j/c (weTO-2,3-di-bromobutane) C2jc (3-bromooctane ethyl a-bromobuty-rate ° ) Pbca (l,l,l-trifluoro-2-chloro-2-bromoethane) Pbcn (dl-2,3-dibromobu-tane) hexagonal R (a-chlorotetrahydropyran) The clathrates for which X-ray crystal structure determinations have been completed are indicated in Table 1. 

Unusual modes of dimerization of cinnamic acids have been found in the solid state photodimerization of the octadecyl esters of these acids. Bolt and co-workers have crystallized this ester of cinnamic acid in three different forms, one of which cyclized to an a-truxilic acid type of dimer, one of which was photo-inert, and one of which gave the 6-truxinic acid dimer. Two crystal forms of the ester of trans-p-chloro-cinnamic acid were isolated, one of which cyclized to an a-truxillic acid, the other being photo-inert. The long-chain ester group presumably modifies the crystal structure, and use of orienting groups of this type may allow the formation of other dimers not usually obtained in solid state dimerizations. 

A one-pot two-step synthesis of hydroxystilbenes with trans selectivity was developed through a modified Perkin reaction between benzaldehydes and phenylacetic acids bearing 4- or 2-hydroxy substitution at the aromatic ring [67]. The reaction was performed under mild conditions in the presence of piperidine-methylimidazole and polyethylene glycol under microwave irradiation. As a result, 71% yield of ( )-4-chloro-4 -hydroxy-3 -methoxystilbene from 4-hydroxy-3-methoxybenzaldehyde and 4-chlorophenylacetic acid was obtained. A microwave-induced one-pot process for the preparation of arylethenes has been patented [118]. For the preparation of a series of arylethenes (I R -R = H, OH, OMe, AcO, halo, NO2 R, R, R = OH, AcO R= H, substituted aryl), reaction of 2- or 4-hydroxy substituted cinnamic adds or derivatives in the presence of a base, under reflux or microwave irradiation, has been used. For example, a mixture of a-phenyl-4-hydroxy-3-methoxycinnamic acid, NaHC03, methylimidazole, and polyethylene glycol was microwaved at 200 W and 180 °C for 10 min to give 96% 4-hydroxy-3-methoxystilbene. 

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