1-Methylcyclohexene: Cyclohexene, 1-methyl

Carbonochloridic acid, methyl ester (79-22-1), 65, 47 1-Methylcyclohexene Cyclohexene, 1-methyl- (591-49-1), 65, 90 Methyl N,N-dichlorocarbamate Carbamlc acid, dichloro-, methyl ester (16487-46-0), 65, 159... 

The rate of transfer hydrogenation also varies markedly with donor structure. For cyclohexene, 1 -methylcyclohexene, l-methyl-4-isopropyl-cyclohexene,and l-methyl-4-f-butyIcycIohexene as donor in the above hydrogenations, after 1 min the reduction was 11, 78, 99, and 99% complete, respectively (97). 

Methyl-l-cyclohexanone, see o-Methylcyclohexanone a -Methylcyclohexene, see 1-Methylcyclohexene 1-Methyl-l-cyclohexene, see 1-Methylcyclohexene Methyl 3-(dimethoxyphosphinyloxy)crotonate, see... 

The rate constants (lO k /l " min ) for bromination of cyclopentene, cyclohexene, and cis-cyclo-octene are 37.5, 6.84, and 0.73 the corresponding values for the 1,2-dimethyl derivatives are 17300, 2080, and 730, The bromination rates for 1-methylcyclohexene, 1-methyl-cis-cyclo-octene, 1-ethylcyclopentene, and 1-ethyl-... 

The purity of the product was determined by the checkers by GLC analysis using the following column and conditions 3-nm by 1.8-m column, 5% free fatty acid phase (FFAP) on acid-washed chromosorb W (60-80 mesh) treated with dimethyldichlorosilane, 90 C (1 min) then 90 to 200 C (15°C per rain). The chromatogram showed a major peak for methyl 2-methyl-l-cyclohexene-l-carboxylate preceded by two minor peaks for methyl 1-cyclohexene-l-carboxylate and l-acetyl-2-methylcyclohexene. The areas of the two impurity peaks were 5-6% and 0.5-2% that of the major peak. The purity of the product seems to depend upon careful temperature control during the reaction. The total amount of the two impurities was 14-21% in runs conducted at about -15 to -20°C or at temperatures below -23°C. 

In the present instance, protonation of the C1-C2 double bond gives a carbo-cation that can react further to give the 1,2 adduct 3-chloro-3-methylcyclohexene and the 1,4 adduct 3-chloro-L-methylcyclohexene. Protonation of the C3-C4 double bond gives a symmetrical carbocation, whose two resonance forms are equivalent. Thus, the 1,2 adduct and the 1,4 adduct have the same structure 6-chloro-l-methyl-cyclohexene. Of the two possible modes of protonation, the first is more likely because it yields a tertiary allylic cation rather than a secondary allylic cation. 

Likewise it is possible to differentiate between substituted and unsubstituted alicycles using inclusion formation with 47 and 48 only the unbranched hydrocarbons are accommodated into the crystal lattices of 47 and 48 (e.g. separation of cyclohexane from methylcyclohexane, or of cyclopentane from methylcyclopentane). This holds also for cycloalkenes (cf. cyclohexene/methylcyclohexene), but not for benzene and its derivatives. Yet, in the latter case no arbitrary number of substituents (methyl groups) and nor any position of the attached substituents at the aromatic nucleus is tolerated on inclusion formation with 46, 47, and 48, dependent on the host molecule (Tables 7 and 8). This opens interesting separation procedures for analytical purposes, for instance the distinction between benzene and toluene or in the field of the isomeric xylenes. 

SYNS FENL-t No. 2633 (-H)-4-ISOPROPENYL-l-METHYLCYCLOHEXENE d-(-l-)-LIMONENE (-l-)-R-LLMONENE d-p-MENTHA-1,8-DIENE j MENTHA-1,8-DIENE D (R)-l-METHYL-4-(l-METHYLETHENYL). CYCLOHEXENE NCI-C55572... 

The microbial oxidation of 1-methylcyclohexene (10) with Aspergillus niger gives ( + )-2-methyI-2-cyclohexenol (11), 2-methyl-2-cyclohexen-6-one (12), and the hydration product, 1-mcthylcy-clohexanol (13), while 4-methylcyclohexene (14) affords rac-6-methyl-2-cyclohexenol (15) and the corresponding ketone (16)361-362. 

Methylation of the lithium enolates derived from cyclohexen-2-one and l,l-bis(methylseleno)ethylli-thium t es place regioselectively but requires the use of more than one equivalent of HI A (S equiv., 0 C, 1 h). The product consists quite exclusively of the trans stereoisomer (99%) with a trace (1%) of the cis (Scheme 140, d and e). The latter can be obtained as a single stereoisomer on hydrolysis of the adduct resulting from the reaction of the same organometallics with 2-methylcyclohexen-2-one... 

The reaction between l,l-bis(methylseleno)-l-propyllithium and other methylcyclohexenones has also been investigated (Scheme 131). ° No adduct was obtained ° from 3-methylcyclohexen-2-ones whatever the conditions used (THF-HMPA or DME), whereas 7-keto selenoacetals are produced from 4-, 3-and 6-methyl-2-cyclohexen-2-ones in yields ranging from 38 to 76% when the reactions are carried out in THF-HMPA (Scheme 131). Yields are lowered by 10% when DME is used instead. °... 

V) in 59% yield and 37% of a mixture of 3-methylcyclohexene (VI) and 4-methyl-cyclohexene (VII). Possible routes to these isomers are suggested in the formulation. In the presence of an adequate amount of lithium, these isomers are reduced fairly... 

AI3-24378 Cyclohexene, 1-methyl-4-(1-methylethyl-idene)- EINECS 209-578-0 FEMA Number 3046 HSDB 5702 4-lsopropylidene-1-methylcyclohexene Isoterp-inene Nofmer TP p-Mentha-1,4(8)-diene Tereben 1,4(8)-Terpadiene Terpinolen Terpinolene UN2541. Oil bp = 186° d = 0.8632 insoluble in H2O, soluble in CsHe, CCI4, freely soluble in EtOH, Et20,... 

---