Cyclo-octene 1-phenyl

Although the n bond is used for coordination in all four compounds, the As—As separation (ca 2.36 A) points to retention of double-bond character. A diarsene carrying a Cp Fe(CO)2 substituent in addition to the well known tri(t-butyl)phenyl group has been isolated as a chromium pentacarbonyl complex, 20, from treatment of Cp Fe(CO)2 As(SiMe3)2 with tri(t-butyl)phenylarsenic dichloride and (cyclo-octene)Cr(CO)5. The compound, which is isostructural with the corresponding diphosphene and phospha-arsene, has an As—As separation of 2.259 A and As—Cr and As—Fe distances of 2.492 and 2.387 A, respectively. On the other hand, the As—As distance in [CpFe(CO)2]-(PhAs—AsPh)[(CO)2FeCp] is 2.456 A and the compound is probably best described as a tetrasubstituted diarsine, rather than a diarsene complex . 

MeOH to give (29), which are 1 1 electrolytes in MeOH. Treatment of PdCl2 with triphenyl(phenylimino)phosphorane and CO in cyclo-octene yields initially a yellow phenyl isocyanide complex which further reacts (Scheme 4) with excess CO to give a ... 

P2B02PtC4oH57, Platinum(II). (3-methoxy-3-oxo-KO-propyl-KC )bis(triethylphos-phine)-, tetraphenylborate(l-), 26 138 P2BPtC44Ht3, Platinum(ll), (q -cyclo-octene)bis(triethylphosphine)-, tetra-phenylborate( 1 —), 26 139 P2C4H 4, Phosphine, 12-ethanediylbis(di-methyl-, nickel complex, 28 101 P2C25H22. Phosphine, methylenebis(di-phenyl-, palladium complex, 28 340 ruthenium complex, 26 276,28 225 P2C26H20, Phosphine, ethynnediylbis(di-phenyl-, ruthenium complex, 26 277, 28 226... 

Distribution measurements show that the silver complex of dr-cyclo-octene is less stable than that of cycloheptene, presumably owing to more ring strain in the latter 129,130). tronr-Cyclooctene is considerably more strained than the cis isomer, and can be separated from it by extraction with 20% aqueous silver nitrate 32), but there are no quantitative measurements of the stability of the silver complex of the tram isomer. The interesting possibility of isomerizing cis to trom-cyclooctene via metal complexes has not yet been achieved. tronr-Cyclooctene has been resolved via its platinum(II) complex with the optically active amine l-phenyl-2-amino-propane (am), 7r-CgH]4PtCl2am. 29). 

Metal-catalysed Isomerizations. The formation of 7r-allylchloropalladium(ii) complexes from a series of cyclopropenes proceeds with symmetrical complexation of the metal to the 7i-bond, and not a-bond cleavage, as the rate-determining step. With substituted cyclopropenes containing a phenyl group at C-3, the it-allyl complex rearranges to indenyl complex either spontaneously or on treatment with triphenyl-phosphine. trans-Chloropalladation of bicyclo[5,l,0]oct-3-ene has been described, and the complex decomposes not to cyclo-octadiene complex, but to a cyclo-octene n-allyl system. ... 

The chemistry of l-methyl-truns-cyclo-octene has been studied. In particular it reacts with acidic methanol to give 1-methoxy-l-methylcyclo-octane, with bromine to give a complex mixture, and with peracid to give its epoxide. On warming in acetic acid it is isomerized to 1-methyl-cis-cyclo-octene, and it reacts with diazomethane and phenyl azide to give cycloaddition products. With 4-phenyl-1,2,4-triazine-3,5-dione, the ene product (121) is obtained. The major difference in reactivity between trans-cyclo-octene and its 1-methyl analogue was found for electrophilic addition reactions where the stability of the incipient 3° cation made the 1-methyl compound more reactive.Transannular products were obtained from the reaction between trans-... 

Substituted heptafulvenes react with DDQ to give 3-substituted 1,2-dicyano-azulenes. 7-Oxoheptafulvene oligomerizes to give the substituted phenyl azulene (181) in solution at room temperature and undergoes [2 + 2] cycloaddition with olefins,e.p. (182) is obtained using ds-cyclo-octene. ... 

Diethylaminosulphur trifluroide converts cyclo-octanol into a mixture of cyclooctyl fluoride (70%) and ds-cyclo-octene (30%). Kinetic data suggests that there is considerable C—Br bond breaking in the transition state for abstraction of bromine from cycloalkyl bromides by phenyl radicals, and that anchimeric assistance by an adjacent bromine atom to bromine abstraction depends upon the accessibility of a trans-periplanar alignment of leaving and neighbouring groups. ... 

Several Himple alkyl- and phenyl-substituted ethylene oxides have wen prepared in good yield by this procedure (Eq. 296). These include l-heptene oxide, 41 1-octene oxide,161 1-hexadeoone oxide, 46 cyclo-licxylothylene oxide,240 1,2-epoxy-4-phenylbutane,1 40 and 1,2-epoxy-J -pi icnylpr opane. 40>1BSo- . ws ... 

Reaction of 2,3-dihydro-l,2-diazepin-4-ol 28 with acetic anhydride forms 2-acctyl-5-ructhyM-phcnyl-l, 2-diazabi-cyclo[3.2.0]heptane6-ol 29 in the presence of base and forms 2-acetyl-6-methyl-7-phenyl-2,3-diaza-8-oxabicy-clo[3.2.1]-6-octene 30 in the absence of base. In addition, bicyclic 29 can be transformed into oxadicyclic 30 by treatment with acid. A study using AMI semi-emperical calculations offers several different routes for these... 

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