2-Phenylpropenal

Allylic acetoxylation of cyclohexene (96) at 80 °C affords 3-acetoxycyclohexene (97) in 67% yield (Scheme 36). It was found that the catalytic double-bond isomerization of 3-phenylpropene proceeds by the action of an electrochemically generated 17-electron Co(II) species [132]. The cobalt(III)-mediated electrooxidative decomposition of chlorinated organics, that is, l,3-dichloro-2-propanol, 2-monochloro-propanol, and so on, has been performed... 

Reduction To the above-prepared solution of NaHTe is added 3-phenylpropenal (0.264 g, 2 mmol) in EtOH (2 mL). The mixture is stirred at room temperature for 4-5 h, then filtered from the formed black Te through Celite and the filtrate evaporated. The residue is purified by distillation, giving the pure product (0.265 g (99%)). 

Conversion of 3-Phenylpropene to l-Brottio-3-phenyl-2-propanone T. Kageyama, Y. Tobito, A. Katoh, V. Ueno, and M. Okawara,... 

Using the same methodology, chiral 3-substituted 3-phenylalkanones can also be prepared34. The precursor chiral allylamines 8 were synthesized from ( )-3-phenylpropenal via the a-aminoallyl cyanide using the Bruylants reaction35. 

The chiral a-cyano allylamines prepared from ( )-3-phenylpropenal, potassium cyanide and (L)-ephcdrinc [(17 ,2S )-2-methylamino-l-phenylpropanol] hydrochloride as a mixture (1 1) of C-l epimers, were deprotonated using 2 equivalents of LDA in THF to give the dilithio compound37. Alkylation at C-3 afforded regioselectively a mixture of (E)- and (Z)-enamines in variable amounts depending on reaction conditions. Diastereoselectivity varied from moderate to excellent. Addition of HMPA and especially lithium iodide improved the diastereoselectivity. De-aggregation is proposed to be the reason for the effect of these additives. 

CH3)2C=CHCH2CH2CH2OH + C6H5CH=CHCHO 5-methyl-4-hexen-1-ol 3-phenylpropenal... 

Rh-diphosphine complex, [Rh(Chiraphos, 106)](C104)2, was used as a catalyst for the intramolecular hydrosilylations of homoallylic silane 107 and silyl allyl ether 108 in acetone at 25°C to give the corresponding 1,4-diol 109 (60% ee, R) in 84% yield and 1,3-diol 110 (with 56% ee, R) in 96% yield, respectively [64] (Scheme 2.7). The Rh-Chiraphos catalyzed reaction of l-(3-phenylpropen-2-yloxy)silacyclohexane (111a) gave diol 112 with 74% ee (R) in 61%... 

Interestingly, enantioselective alkylation reactions [64] were also developed using, for instance, Cu(OTf)2, [65], [Cu(SbF6)2, Zn(OTf)2] [66], Cu(C104)2-6H20 [67] or Sc (OTf)3 [68] in combination with diverse chiral ligands. Remarkably, organocatalytic alkylations of pyrroles, indoles and anilines by 3-phenylpropenal have been also developed [69]. 

Phenylpropenal reacted with ethylamine in the presence hydrogen and Pt as catalyst and BaS04 and N-ethyl-3,3 -diphenyldipropylamine (alverine) was obtained. 

The double conjugate addition of sulfide to the dienones 540 leads to 3-aryltetrahydrothiopyran-4-ones. The dienones are obtained from the reaction of electron-rich a-bromostyrenes with ot,(3-unsaturated aldehydes. When the latter is 3-phenylpropenal, a diastereomeric mixture resulted in which the trans-isovaet was predominant (Scheme 223) <2006EJ04044>. 

Terminal alkenes are oxidized with negligible rearrangement to give the 3-acyloxy species. - However, oxidation of internal alkenes, including cycloalkenes, may result in substantial or exclusive rearrangement. Most notable is the reaction of 1-phenylpropene exclusively to give 3-acetoxy-3-phenylpropene, in which deconjugation of the double bond t es place (equation 20). ... 

Over-oxidation occurs if the solution is permitted to become basic. For example, 3-phenylpropene gives igjproximately equal amounts of phenylacetic acid and benzoic acid when oxidiz under phase transfer conditions using a two-phase benzene/water solvent system. However, when acetic acid is added, the yield of phenylacetic acid increases to 80%. ... 

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