1-Phenylpropene

The oxidative coupling of alkenes which have two substituents at the 2 posi-tion, such as isobutylene, styrene, 2-phenylpropene, 1,1-diphenylethylene, and methyl methacrylate, takes place to give the 1,1,4.4-tetrasubstituted butadienes 285 by the action of Pd(OAc)2 or PdCF in the presence of sodium acetate[255-257]. Oxidation of styrene with Pd(OAc)2 produces 1.4-diphenylbutadiene (285, R = H) as a main product and a- and /3-acetoxystyrenes as minor pro-ducts[258]. Prolonged oxidation of the primary coupling product 285 (R = Me) of 2-phenylpropene with an excess of Pd(OAc)2 leads slowly to p-... 

Subtle ligand changes have pronounced effects in hydroboration of 1,1-disubstituted alkenes. Addition of HBcat across the C=C bond in 2,3,3-trimethyl-l-butene is catalyzed by [Rh(COD)Cl]2/DIOP at —5°C affording 2-t-butyl-l-propanol in 69% ee upon oxidation. In the case of 2-phenylpropene, [Rh(C2H4)2Cl]2 combines with either DIOP or BINAP to provide higher enantiomeric excesses than with [Rh(COD)Cl]2.46... 

Popovic, M. et al., Investigating the role of 2-phenylpropenal in felbamate-induced idiosyncratic drug reactions. Chern. Res. Toxicol., 17, 1568, 2004... 

Preliminary studies on catalytic osmylation were reported by Kokubo and co-workers who used bovine serum albumin, 0s04, and t-butylhydroperoxide as the oxidant. Turnover numbers up to 40 and an e.e. for 2-phenylpropene of 68% was achieved [23], Apparently the protein binds to osmium via nitrogen donors, but as different sites may be available this may lower the e.e. 

Synonyms AI3-18133 AMS BRN 0969405 CCRIS 6067 EINECS 202-705-0 Isopropenyl-benzene (1-Methylethenyl)benzene 1-Methyl-1-phenylethylene a-Methylstyrol NSC 9400 Ortho brush killer A 2-Phenylpropene P-Phenylpropene 2-Phenylpropylene p Phenylpropylene UN 2303. 

Phenylpropane, see Isopropylbenzene 2-Phenylpropene, see a-Methylstyrene p-Phenylpropene, see a-Methylstyrene 2-Phenylpropylene, see a-Methylstyrene p-Phenylpropylene, see a-Methylstyrene o-Phenylpyrene, see Indeno[l,2,3-caf p3U ene Penyltrimethylmethane, see ferf-Butylbenzene Philex, see Trichloroethylene... 

Aryl-substituted aliphatic compounds show additional elimination reactions in the side chain resulting in perfluoroalkenylaromatics, e. g. formation of perfluoro(2-phenylpropene) (3).127,128... 

According to the foregoing analysis, the maximum number of lines observable for the A and B resonances is sixteen (8 for A and 8 for B). In fact, only eleven are visible (6 for A and 5 for B), which means that some of the sixteen possible lines must overlap. Without examining all possibilities, we can see that the actual situation can be reproduced if JAB = JBC = 2JAC =1.5 Hz. Figure 9-39 shows that these values lead to five coincidences and eleven lines. There is no simple explanation of why JAB = JBC = 2.7AC. The only structure that is consistent with 7ab = 1.5 Hz is 13, or 2-phenylpropene the other possibilities are excluded because JAB should be about 10 Hz for 12 and 16 Hz for 11. 

Exercise 9-34 a. Show how the assignment of JAB = JBC = 2JA0 leads to the prediction of four equally spaced and equally intense lines for the methyl resonance of 2-phenylpropene. 

A remarkable level of ( +)-NLE has been observed in the catalytic ene reaction. For instance, the glyoxylate-ene reaction with 2-phenylpropene using a catalyst prepared from BINOL with 33.0% ee provides the corresponding ene product with 91.4% ee in 92% chemical yield (Scheme... 

IEs were used to verify a tautomeric equilibrium in 2-phenylpropenal-c/ (47 + 48) and to distinguish this mixture from a symmetric structure with a hydrogen centered within the hydrogen bond.120 According to 13C and H chemical shifts, the equilibrium favors 48. From the temperature dependence AH° was estimated as -27 cm-1, or -0.08 kcal mol-1. Because both tautomers have the same conjugate base, 47, which is less stable, must be the stronger acid, owing to a secondary deuterium IE. 

B-9. Which sequence of steps describes the best synthesis of 2-phenylpropene ... 

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