4-chlorocinnamic acid

This procedure has been used by the submitters and others to prepare the following cinnamic acids from substituted benzal-dehydes o-nitrocinnamic acid (70%),2 -nitrocinnamic acid (77%),2 w-cyanocinnamic acid (71%),3 o-chlorocinnamic acid (82%),4 m-chlorocinnamic acid (53%),4 -chlorocinnamic acid (73%),4 2,4-dichlorocinnamic acid (70%),4 3,4-dichlorocinnamic acid (81%),4 w-bromocinnamic acid (31%),4 -methoxycinnamic acid (60%),4 and 3,4-dimethoxycinnamic acid (77%).4... 

The second way of synthesizing baclofen is started from ethyl ester of 4-chlorocinnamic acid. Adding nitromethane to this in the presence of base gives ethyl ester of j3-(4-chlorophenyl)-7-nitrobutyric acid (15.3.6), the nitro group of which is reduced by hydrogen over Raney nickel to the ethyl ester of j3-(4-chlorophenyl)-7-aminobutyric acid (15.3.7), which is further hydrolyzed into the desired baclofen (15.3.5) [29]. 

Ch1orocinnamic acid, A075 L-Chlorocinnamic acid, AO76 2-Ch1orocyc1ohexanone, AH57... 

Fig. 2.3. Chromatogram of 2 jil aliquois of a test mixture on a 100 x 2.1 mm column of 3.5 jcm SymmetryShield RPI8. Mobile phase A was 0.191 v/v formic acid in water and mobile phase B was 0.19 v/v formic acid in acetonitrile-water (95 5 v/v). Gradicnl time was 5 min and the flow rate was 1.5 ml/min. The temperature was 60°C. giving a starting pressure of ca. 300 bar (4350 psi). Detection was at 215 nm. Peak identities pyridine, quinine, ben/yl alcohol, phenol, nortriptyline, acetophenone. 3-methyl-4-nitrobenzoic acid, methyl salicylaldehyde, 4-chlorocinnamic acid and octanophenone.

In the reduction of p-chlorocinnamic acid with an excess of sodium hypophosphite and palladium (equation 47), the double bond is saturated and the hydrogenolysis of chlorine occurs. With one equivalent of the hypophosphite, only saturation of the double bond takes place, and p-chlorohydrocinnamic acid is obtained after 1.5 h. ... 

C9H6CIN02 5-chloroindole-2-carboxylic acid 10517-21-2 25.00 1.3706 2 15968 C9H7CI02 trans-O Chlorocinnamic acid 939-58-2 25.00 1.2772 2... 

C9H6CIN04 2-(4-chloro-2-nitrophenyl)malondialdehyde 205744-82-7 25.00 1.4785 2 15972 C9H7CI02 2-chlorocinnamic acid, predominantly trans 3752-25-8 25.00 1.2772 2... 

CH.NOji It yel crysts, mp 98-99° readily sol in org soivs except petr eth insol in w was prepd by nitrating 2-nitro 4-chlorocinnamic acid with HN03(d 1.52), or by reacting 2-nitro-4-chloro-benzaldehyde with nitromethane KOH in MeOH-KOH(Refs 2 4) and... 

A physician wishes to prepare a buffer solution at pH = 3.82 that efficiently resists changes in pH yet contains only small concentrations of the buffering agents. Determine which one of the following weak acids, together with its sodium salt, would probably be best to use w-chloroben-zoic acid, = 1.04 X 10"" p-chlorocinnamic acid, = 3.89 X 10 2,5-dihydroxybenzoic acid, = 1.08 X 10 or acetoacetic acid, = 2.62 X 10 ". Explain. 

Figure 10. Crystal data of (3-4, stereoscopic packing diagram with (100) on top of the isomorphous 4-chlorocinnamic acid, and van der Waals surfaces of 4 and 6 with schematic representation of the fit by two turns of 6 around 90° and 60°.

Chlorophenyl)propionic acid A solution of 4-chlorocinnamic acid (5 g) in tetralin (180 ml) containing palladium black (1 g) is heated at the boiling point for 1.5 h in a Kjeldahl flask under an air condenser. The side chain is then completely reduced. The catalyst is filtered off, the acid components are removed from the filtrate in sodium carbonate solution, adhering tetralin is removed from the alkaline solution by ether, the alkaline solution is acidified by hydrochloric acid, and the 3-(p-chlorophenyl)propionic acid that separates is taken up in ether. On evaporation, the pure 3-(p-chlorophenyl)propionic acid of m.p. 123° is obtained. 

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