1 -Pheny 1-2-buten

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. 

The tosylate of (2>RP35)-3-phenyl-2-butanol undergoes E2 elimination on treatment with sodium ethoxide to yield (Z)-2-pheny)-2-butene. Explain, using Newman projections. 

Z)-1,2-diphenyl-1 -[4-[2-(dimethy(amfno ethoxy]pheny) -1 -buten-4-ol (III)... 

Vollhardt s investigations100 into electrocyclic transformations on a CpCo template produced the following unusual result. After photolysis of CpCo(CO)2 in the presence of the tosyl hydrazone of trans-4-pheny -3-buten-2-one, the only isolated product was the vinylketene complex 123. Note that the tricarbonyliron analogue of this complex has also been isolated.3,87 The mechanism of formation was not discussed, but it seems likely that the ketene carbonyl originated as a carbonyl ligand that replaced the hydrazone moiety, perhaps via a vinylcarbene intermediate. 

OTf Pc pda Ph phen phenba triflate = trifluoromethanesulfonate phthalocyanato(2 -) 1,2-pheny lenediaminato(2 -) phenyl 1,10-phenanthroline NJV -l, 2-phenylenebis[2-acetyl-l -amino-1 -buten-3-onato( 1 -)]... 

Z)-2-Phenyl-2-butene. (Z)-2-pheny 1-2-butene is not as stable as its (E) isomer. When Co >(CO)8 is used, results are the same with the (E) stereoisomer. However, when rhodium is used, isomer selectivity changes (Table VIII). The main isomeric aldehyde is the erythro di-astereoisomer which represents 33.9% of the whole mixture. Aldehyde 27 is formed in nearly the same ratio (32.9% ) while 6.8% and 4.4% of aldehyde 26 and the threo diastereoisomer are formed. 

Effect of the Stereochemistry. With rhodium, the geometry of molecules such as (E)- and (Z)-2-pheny 1-2-butenes influences both the distribution of diastereoisomers formed by addition of CHO group on the ft carbon and the distribution of aldehydic isomers. Depending on the starting (E) or (Z) stereoisomer, one of the two diastereoisomers predominates this implies some degree of stereospecificity in the hydroformylation reaction. On the other hand, when Co2(CO)8 is used, no stereospecificity in the hydroformyaltion reaction is observed. It is thus possible to get information about the stereochemistry of the hydro-... 

The other feature of hydroformylation of ( )- and (Z)-2-pheny 1-2-butenes concerns the distribution of aldehydic isomers 26 and 27. With Co2(CO)8, whatever the stereochemistry of the olefin, the distribution of these two aldehydes is exactly the same. On the other hand, with Rh/Al203 the reaction is more or less oriented towards the formation of one of the aldehydic isomers. Moreover, the phenomenon is more striking with (Z) than with (E) stereoisomer. 

Butene 2-Fluoro-3-methyl-l-phenyltliio- ElOb,. 378 (In+ Ar — S-NR,/BF3) 1-Pentene 2-Fluoro-l-pheny thio-E10b,. 378 (In + Ar —S NR,/ BF )... 

Die 4-Oxo-4-phenyl-butansaure liefert in Gegenwart von Schwefeltrioxid/Dimethyl-formamid unter Lactonisierung 2-Ethoxy methy kn-4-pheny 1-3-buten-4-olid zu 75°/o10 ... 

Hydroboration of representative olefins—such as 1-octene, 1-decene, styrene, o -methyl-styrene, 2-methyl-1-pentene, c/5 -4-methyl-2-pentene, 2-methy 1-2-butene, of-pinene, cyclohexene, 3-carene, 1-pheny 1-2-methyl-1-propene, 2,3-dimethy 1-2-butene and 1,2-dimethylcyclopentene—with dioxane-BH2Cl was carried out in dioxane and dichloromethane solvents. The procedure followed for all the olefins in both the solvents are same. The procedure followed for 1-decene in dichloromethane is representative. 

Reactions of alkenes and vinylarenes catalyzed by palladium complexes of axially chiral biaryhnonophosphines generate branched products, and these products are formed with high ee. As shown in Equation 16.36, the hydrosilylation of hexene, 4-pheny 1-1-butene, and... 

Liebler DC, Guengerich FP(1983) Olefin oxidation by cytochrome P-450 evidence for group migration in catalytic intermediates formed with vinylidene chloride and trans-l-pheny 1-1-butene. Bioehemistry 22 5482-5489... 

Che has reported the tandem hydroamination/hydroarylation of aromatic amines wirh terminal alkynes to form dihydroquinolines in which 1 equiv of aniline combines with 2 equiv of alkyne [23]. For example, reaction of 3-methoxyanilme with pheny-lacetylene (5 equiv) and a catalytic 1 1 mixture of the gold(I) N-heterocydic carbene complex (IPr)AuCl (IPr= l,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidine) and AgOTf at 150 °C under microwave irradiation led to isolation of dihydroquinoline 21 in 82 % yield (Eq. (11.15)). Alternatively, reaction of o-acetylaniline with pheny-lacetylene catalyzed by a mixture of (IPr)AuCl and AgOTf at 150 °C led to isolation of the quinoline derivative 22 in 93% yield via incorporation of a single equivalent of alkyne (Eq. (11.16)). Arcadi has reported the gold(IlI)-catalyzed hydroamination/ hydroarylation of 2-alkynylanilines with a,p-enones to form C3-alkyl indoles [24]. As an example of this transformation, treatment of 2-(phenylethynyl)aniline with 4-phenyl-3-buten-2-one and a catalytic amount of sodium tetrachloroaurate dihydrate in ethanol at 30°C formed 1,2,3-trisubstituted indole 23 in 88% yield (Eq. (11.17)). 

Figure 4. DRIFT spectra of chemically modified silicas. A) 4-pheny-l-butene and...

Phenyl-1-butene l-Pheny(-2-buten-1-one i / 75 4-Phenyl-3-buten 2-one 4-Phenyl-3-butyn-2-one... 

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