2-Methyl-l-octene

Unlike the insertion of 2-monosubstituted alkenyl carbenoids (69, 70, and 73), the reaction of 2,2-disubstituted alkenyl carbenoids with alkenyl zirconocene chlorides afforded the expected products as a mixture of stereoisomers. Thus, when 77, derived from the deprotonation of the stereodefined E-l-chloro-2-methyl-l-octene 76, was reacted with -l-hexenylzirconocene chloride 78 at low temperature, a partial inversion of configuration at the alkenyl carbenoid center occurred before or during the rearrangement to afford the expected metalated diene 79 with an E Z isomeric ratio of 58 42 after hydrolysis (see 80, Scheme 27) [53]. The poor stereocontrol was attributed to the metal-assisted ionization [58-60], which promotes the interconversion of the E- to the Z-alkenyl carbenoids 77. The latter occurs at a rate comparable with that of the insertion into organozirconocene chloride, and hence this is responsible for the loss of stereochemistry. 

MethyI-2-naphthoic acid, 243 a-Methylnitriles, 334 10-Methyl-A O-2-octalol, 235 10-Methyl-A1 ( )-2-octalone, 300 2-Methyl-l-octene, 369... 

CN 5-[Hexahydro-5-hydroxy-4-(3-hydroxy-4-methyl-l-octen-6-ynyl)-2(l//)-pentalenylidene]pentanoic acid... 

Effect of Hydroperoxide Structure. The reactivity of various hydroperoxides was studied with 2-octene and 2-methyl-l-pentene (Table VII). The yield of epoxide was quantiative. The data show that the substitution of the electron-withdrawing nitro groups in the para-position of cumene hydroperoxide markedly increases the reaction rate. The order of reactivity is p-nitrocumene > cumene > tert-butyl hydroperoxide. 

Under unoptimized conditions, the reaction uniformly gives (/ )-2-methyl-l-alkanols with 65-75% ee. In the case of 1-octene, running the reaction at 0°C in 1,1-dichloro-ethane has improved the enantioselectivity from 72 to 81% ee. 

Chemical Name Isoquinolinium, 2,2 -((l,8-dioxo-4-octene-l,8-diyl)bis(oxy-3,l-propanediyl))bis(l,2,3,4-tetrahydro-6,7-dimethoxy-2-methyl-l-((3,4,5-trimethoxyphenyl)methyl)-, dichloride, (R-(R, R -(E)))-... 

Dichloroanisole 2.3.6- Trichloroanisole 2.4.6- Trichloroanisole 2.3.4.6- Tetrachloroanisole Pentachloroanisole 2.4.6- Tribromoanisole Geosmin 2-Methylisoborneol l-Octene-3-ol Octa-1,3-diene a-Terpineol 4.4.6- Tri methyl-1,3-dioxane... 

The phenyl tellurium tribromide can be prepared in situ from diphenyl ditellurium and bromine. Olefins thus far investigated include isobutene, (E)- and (Z) -butene, 1 -hexene, 2-methyl-l-pentene, 1-octene, (E)- and (Z)-4-octene, 1-decene, phenylethene, 1-phenyl-I-methylethene, cyclopentene, cyclohexene, cycloheptene, and cyclooctene. Most of the reactions were carried out with phenyl tellurium tribromide in methanol. 

The stereohomogeneous (Z)-crotyltrimethylsilane reacts with 1-hexene to give 3-methyl-4-(trimethylsilyl)methyl-l-octene as a mixture of two diastereomers in 25% yield [Eq. (4)].2 The diastereomeric products possess a methyl group at the carbon a to the double bond, indicating that an allylic inversion occurs during the allylsilylation.13 17... 

Moreover, cyclization of(Z)-2-methyl-5-octen-l-ol (3) leads mainly to the 2.5-rran.s-disubstituted tetrahydro-2//-pyran with high 1,4-asymmetric induction and the diequatorial arrangement is preferred81. 

After the discovery of MVOC, these compounds were also thought to provoke certain symptoms of sick building syndrome in view of their similarity to commonly found VOC, which may cause symptoms like headache and dizziness. However, since MVOC concentrations are normally 2-3 decimal powers lower than those of comparable VOC, these low concentrations should not be expected to have any effects in indoor air [75]. Mutagenic, cytotoxic or genotoxic effects were not found in vitro in mammalian cells with typical MVOC like 2-pentylfuran, 1-butanol, 2-butanone, 3-methyl-l-butanol, 2-methyl-l-propanol, 2-hexanone, 2-heptanone, l-octen-3-ol, 3-octanone or... 

Various 1,2-bifunctionalized alkenes containing heteroatoms are prepared by addition to alkynes. Thiophosphorylation of 1-octyne with phosphorothiolate 131 provided (Z)-l-(diphenoxyphosphinyl)-2-(phenylthio)-l-octene in good yield [40]. A useful synthetic method for (Z)-3-phenylthioacrylate derivative is the Pd-catalyzed thioesterification of 1-alkynes with 6)-methyl S-phenyl thiocarbonate (132). Addition of 132 to 1-octyne using Pd(PCy3)2 as a catalyst afforded methyl (Z)-3-phenylthio-2-nonenoate in 86% yield [41]. (Z)-l,2-Bis(phenylthio)alkene was prepared in good yield by stereoselective Pd-catalyzed addition of (PhS)2 (3) to 1-alkyne [2]. 

Volatile decomposition products from autoxidized linoleic acid and methyl linoleate were characterized for their intense aroma and flavor impact by capillary gas chromatography-olfactometry. This technique involves sniffing the gas chromatograph effluent after stepwise dilution of the volatile extract. The most intense volatiles included hexanal, c/ -2-octenal, /ra. s-2-nonenal, l-octene-3-one, 3-octene-2-one and trans-l-ociQmX (Table 4.2). This analytical approach does not, however, consider the effects of complex interactions of volatiles occurring in mixtures produced in oxidized food lipids. 

The relative rates of [Mo(CO)6]-catalyzed epoxidation of olefins by erf-butyl hydroperoxide in benzene were found to be in the order allyl chloride (0.1) 1-octene (1.0) < styrene (1.3) < 2-methyl-l-heptene (9) < cyclohexene (13) < cis-2-octene (14), norbornene (14) < 2-methyl-2-heptene (75). Thus, electron donation in the form of alkyl groups about the double bond accelerates the reaction rate whereas electron withdrawal tends to retard it [379]. 

Using benzene solvent and a variety of initiators, Frank " described the preparation and properties of a-olefin-MA copolymers from propylene, 1-butene, isobutene, cis- and m 5-2-butene, 2-methyl-l-pentene, 2,4,4-trimethyl-1-pentene, 1-hexene, and 1-octene. In order to characterize the materials, the [r/]-Mvv relationship was elucidated for the polymers ... 

PP and a-PP decomposed into a large number of aliphatic compounds without a residue. Some 96 wt% of the carbon in PP and 97 wt% of the carbon in a-PP was converted to volatile organic compounds such as alkanes, alkenes and dienes. Major compounds are, for instance, C9 hydrocarbons, such as 2-methyl-1-octene, 2-methyl-2-octene, 2-methyl-4-octene, 2,4-dimethyl-l-heptene and 2,6-dimethyl-2,4-heptadiene. 

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