Benzylacetic acid

Carbonylation of phenethyl bromide catalysed by Co2(CO)8 alone or modified either with tppts or tppms yielded products of double- and mono-carbonylation, (benzylpyruvic and benzylacetic acid, respectively) at a concentration of 8 mol% cobalt, 85°C and 20 bar CO under basic conditions in an H20/tBuOH (14/1) solvent mixture (Figure 13).475>476 The reaction rates exhibited by Co2(CO)8 were comparable with the Co2(CO)6(tppts)2 catalyst but replacement of tppts by tppms gave rise to a dramatic decrease in catalytic activity.475 Substantially different double/mono carbonylation (d/m ratios) were observed with Co2(CO)8, Co2(CO)e(tppts)2 and Co2(CO)6(tppms)2 7.3, 2.1 and 0.3, respectively, which... 

W C HggH -ICH OOHl Benzylacetic acid, 3-Phenylpropanoic acid OH... 

So far, easily available alkyl halides have not been applied to biphasic carbonyla-tions. However, the carbonylation of phenethyl bromide with hydrophilic cobalt catalysts to give benzylpyruvic acid (BPA) and benzylacetic acid (BAA) was investigated (Eq. 11) [21]. 

Beilstein Handbook Reference) AI3-00892 Benzenepropanoic acid Benzeneproplonic acid Benzylacetic acid BRN 0907515 CCRIS 3199 Dihydrocinnamic acid EINECS 207-924-5 FEMA No. 2889 Hydrocinnamic acid NSC 9272 Phenylpropanoic acid 3-Phenylpropanoic acid p-Phenylpropionic acid 3-Phenylpropionic acid. Fixative for perfumes, flavoring. Solid mp = 47-48° bp n 280° Xm = 247, 252, 257, 260, 263, 267 nm (MeOH) soluble in H2O (5.8 g/l), EtOH, Et20, CCl4, CHCI3, CS2, very soluble in CeHe, Greeff R.W. Co. Janssen Chimica Penta Mfg. 

Benzylacetic acid. See Hydrocinnamic acid Benzyl acetoacetate... 

Synonyms Benzenepropanoic acid Benzenepropionic acid Benzylacetic acid Dihydrocinnamic acid Phenylpropanoic acid 3-Phenylpropanoic acid Phenylpropionic acid 3-Phenylpropionic acid P-Phenylpropionic acid... 

Mono- and double carbonylation of phenetyl bromide with cobalt-phosphine catalysts afforded benzylacetic (Baa) and benzylpymvic (Bpa) acids respectively [23] (Scheme 5.5). The highest yield of benzylpymvic acid (75 %) was obtained with [Co2(CO)8], while addition of the water soluble phosphines TPPMS or TPPTS decreased both the yield of carbonylated products and the selectivity to Bpa. 

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