2-Ethyl-4-methyl-l-pentene

Note that there is a six-carbon chain in 2-ethyl-3-methyl-l-pentene. However, because the longest chain that contains the carbon-carbon double bond has only five carbons, the parent hydrocarbon is pentane, and we name the molecule as a disubstituted 1-pentene. 

Perfluoro-2 (1 ethyl 1 methylpropyl)-3-methyl-l-pentene, the major hex-amer of tetrafluoroethylene, reacts with sodium methoxide to yield an ester, whereas a stable crowded ketene is formed by reaction with sodium hydroxide [2d] (equation 23)... 

The enthalpy of formation of the 2-ethylbutadiene is taken from Reference 8. The enthalpy of formation of the monoolefin products, 3-methyl-l-pentene and 2-ethyl-l-butene, are derived from Reference 11. 

The a-nucleated polypropylene is used for power cable insulatioa A polymeric a-nucle-ating agent comprises monomer units derived from a vinyl compound. The vinyl compound is selected from the group consisting of vinyl cyclohexane, vinyl cyclopentane, vinyl 2-methyl cyclohexane and vinyl noibomene, 3-methyl-l-pentene, styrene, p-methyl-styrene, 4-methyl-1-pentene, 3 -methyl-l-butene, and 3-ethyl-l-hexene. Nucleating agent is present in the polymer composition in the amount of 0.0001 to 0.2 wt%. ... 

Scheme 90 Cathodic addition of ethyl bromide to 2-methyl-l -penten-3-one.

UN 1897, see Tetrachloroethylene UN 1915, see Cyclohexanone UN 1916, see Bis(2-chloroethoxy)methane. Bis(2-chloroethyl) ether UN 1917, see Ethyl acrylate UN 1918, see Isopropylbenzene UN 1919, see Methyl acrylate UN 1920, see Nonane UN 1941, see Dibromodiflnoromethane UN 1969, see 2-Methylpropane UN 1978, see Propane UN 1991, see Chloroprene UN 1992, see 2-Chloroethyl vinyl ether UN 1993, see 2,3-Dimethylpentane, 3,3-Dimethylpentane, 4 Ethylmorpholine, 2-Ethylthiophene, Indan, Isobutylbenzene, 2-Methylhexane, 3-Methylhexane, 2-Methyl 1 pentene, 4-Methyl-l-pentene, 1,4-Pentadiene, cis 2 Pentene, frans-2-Pentene, 1,2,4-Trimethylbenzene UN 2018, see 4-Chloroaniline UN 2019, see 4-Chloroaniline... 

The hydroformylation of several olefins in the presence of Co2(CO)8 under high carbon monoxide pressure is reported. (S)-5-Methylheptanal (75%) and (S)-3-ethylhexanal (4.8%) were products from (- -)(S)-4-methyl-2-hexene with optical yields of 94 and 72%, respectively. The main products from ( -)(8)-2,2,5-trimethyl-3-heptene were (S)-3-ethyl-6,6-di-methylheptanal (56.6%) and (R)-4,7,7-trimethyloctanal (41.2%) obtained with optical yields of 74 and 62%, respectively. (R)(S)-3-Ethyl-6,6-dimethylheptanal (3.5% ) and (R)(S)-4,7,7-trimethyloctanal (93.5%) were formed from (R)(S)-3,6,6-trimethyl-l-heptene. (+/S)-l-Phenyl-3-methyl-1-pentene, under oxo conditions, was almost completely hydrogenated to (- -)(S)-l-phenyl-3-methylpentane with 100% optical yield. 3-(Methyl-d3)-l-butene-4-d3 gave 4-(methyl-d3)pentarwl-5-d3 (92%), 2-methyl-3-(methyl-d3)-butanal-4-d3 (3.7%), 3-(methyl-d3)pentanal-2-d2,3-d1 (4.3%) with practically 100% retention of deuterium. The reaction mechanism is discussed on the basis of these results. 

Similar unsatisfactory results, usually with even lower inductions are obtained with other terminal aliphatic alkenes such as 1-pentene, 2-methy]-l -butene, 3-methyl-l -butene, 2,3-dimethyl-l-butene, 3,3-dimethyl-l-butene, 2,3,3-trimethyl-l-butene, 2-ethyl-l-hexene, I-hex-ene and 1-octene (Table 1). 

When the enantiomerically enriched alkene (5)-3-methyl-l-hexene is employed, 3-ethyl-l-hexanal is formed with 70% retention of configuration together with 4-methyl-l-heptanal and 2,3-dimethyl-l-hexanal, in spite of the fact that the precursor of this product should be achiral 2-ethyl-l-pentene generated through isomerization of (5)-3-methyl-l-hexene. In order to accommodate this result, a 1,2-hydrogen shift mechanism has been proposed that does not include a true cr carbon-Co bond and is faster than the dissociation of olefin from the olefin-Co complex, which appears to be generally accepted. 

A solution of 16.0 g a-allylbutyrophenone in 180 mL rm-butyl alcohol was irradiated under nitrogen in an immersion well with a Pyrex-filtered 450-W Hanovia mercury arc until < 10% of the starting ketone remained. GC analysis showed six products, but none of products was identified as 3-methyl-l-benzoylcyclopentane. After stripping of the solvent, the residue was chromatographed on neutral alumina with cyclohexane/CHCl3 (1 1) as the eluent to afford five components, of which the first three were further purified by GC through a column packed with 15% QF-1 and 3% Carbowax. These compounds were 1 -phenyl-3-penten-1 -one, 4-phenyl-3-ethyl-4-pentenal, 1 -phenyl-2-aUylcyclobutanol, 2-phenylbicyclo[2.2. l]heptanol-2, and 3-phenyl-4-ethyl-3-cyclopentenol. 

Enones A, ethyl 6-methyl-2-oxo-3-cyclohexene-l-carboxylate B, 3-penten-2-one ... 

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