2-Phenyl-2-butene

Analogous bifunctionalizations of cyclohexene, 1-phenyl-2-butene and cyclo-pentene to l-halo-2-acetamido (acetoxy) adducts are reported by Weinberg and... 

Disubstituted furans (130) can be obtained by treatment of /3-alkoxy- and /3-arylthio-a,/3-unsaturated ketones, for example 3-methoxy-1-phenyl-2-buten-1-one (128) or 3-ethylthio-l-phenyl-2-buten-l-one (129), with dimethylsulfonium methylide (79JHC815, 69TL679), The possible reaction pathway (Scheme 27) shows the initially formed epoxides as rearranging by ring opening at the tertiary epoxide carbon atom. 

The oxidation of alkylbenzenes also produced sec-alcohols and ketones, with no reaction at tertiary and primary carbons. At variance with the rule that double bonds are preferentially oxidized over other functionalities, side-chain epoxidation had to compete with aromahc hydroxylation in the oxidation of a-methylstyrene, 1-phenyl-2-butene and 4-phenyl-1-butene [60]. 

Phenyl-1-butene 1-Phenyl-2-buten-1-one /zazi5-4-Phenyl-3-buten-2-one 4-Phenyl-3-butyn-2-one... 

The Ti state (but not the Si state) of toluene sensitizes the photoisomerization of both ( )- and (Z)-2-heptene. Direct irradiation of either isomer of 1-phenyl-2-butene leads to photoisomerization. The fluorescence spectrum of l-phenyl-2-butene is simitar in shape to that of toluene but is slightly reduced in intensity. However, phosphorescence from 1-pheny 1-2-butene was not detected under conditions in which phosphoresence from toluene could readily be observed. Propose an explanation for the photoisomerization of l-phenyl-2-butene upon direct irradiation that is consistent with these observations. 

An a,p-unsaturated ketone can contribute as both a Michael donor and a Michael acceptor at the same time. There are cases in which a PTC catalyst has served for the enantioselective dimerisation of a,(3-unsaturated ketones under phase-transfer conditions. In 2004, Corey and coworkers demonstrated a simple and practical pathway to chiral a-alkyl-ated y-keto acids, which are important intermediates for the preparation of peptide isosteres by dimerisation, through a Michael reaction of 1-phenyl-2-buten-l-one (57) with itself. Subsequently, the Bella group reported the asymmetric dimerisation of cyclohexenone (60), catalysed by the newly prepared PTC catalyst 7f with good enantioselectivity (up to 92% enantiomeric excess), and no byproducts or regioisomers were observed (Scheme 16.18). ... 

To illustrate, consider the synthesis of (Z)-1 -phenyl-2-butene. A major consideration— controlling the stereochemistry of the double bond—can be achieved by catalytic hydrogenation of the corresponding alkyne. 

Mercapto-1 -phenyl-2-buten-1 -one, M-00044 A-[[(2-Mercaptophenyl)imino]methyl]phenol,... 

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