2- methylcyclohexyl

Base-promoted E2 elimination involves simultaneous loss of and X from neighboring carbons. Applying this rule to 2-methylcyclohexyl tosylate suggests that two different products might form, but the actual situation is more complicated. One tosylate isomer gives only one of the two possible alkenes, while the other gives both. 

Examine all of the low-energy (within. 004 au or 3 kcal/ mol of the lowest-energy conformer) conformers of cis-2-methylcyclohexyl tosylate. Identify every conformer that can undergo anti elimination of OTs and H+, and predict the alkene that will be produced. What alkenes will be obtained from the cis tosylate ... 

Analyze the low-energy conformers of trans-2-methylcyclohexyl tosylate in the same way. What alkenes will be obtained from the trans tosylate ... 

With nonracemic chiral diazoacetates the insertion process occurs with evident match/mismatch characteristics. This has been demonstrated in reactions of optically pure 2-methylcyclohexyl diazoacetates (Eq. 9) [85] and in carbon-hydrogen insertion reactions of steroidal diazoacetates (Eq. 10) [86], as well as with the synthesis of pyrrolizidines 36 and 37 [84]. The mechanistic preference for formation of a /J-lactone in Eq. 10 over insertion into the 4-position is not clear,but there are other examples of /J-lactone formation [87]. In these and related examples, selectivities in match/mismatch examples are high, and future investigations are anticipated to show even greater applicability. 

The preferred stereoelectronic arrangement is perpendicular alignment of the acetate with respect to the double bond. For example, the cis and trans isomers of 1-vinyl-2-methylcyclohexyl acetate show divergent stereochemical results. Only the exocyclic E-isomer is formed from the cis compound, whereas the trans compound gives a 1 1 mixture of the E- and Z-isomers. This is the result of a strongly preferred conformation for the cis isomer, as opposed to a mixture of conformations for the trans isomer.32... 

These compounds are named as cycloalkylalkanes. Examples are dicyclohexylmethane, 1,5-dicyclopenfylpentane, l-cyclohexyl-3-(2-methylcyclohexyl)propane. 

These studies were subsequently extended to the analogous stannanes and the 3-methyl and 2-methylcyclohexyl bromides (Table 9)47. The MesSnLi reactions, as expected, afforded similar ratios of isomeric product from a given set of stereoisomeric bromides. However, Pt SnLi led to clean inversion with 4-methyl and trans-3-methylcyclohexyl bromides. Evidently, the Ph3Sn radical is not easily formed under these conditions. 

CASRN 1982-49-6 molecular formula C14H20N2O FW 232.30 Soil. A fungus and two Pseudomonas spp. isolated from soil degraded siduron to form the major metabolites l-(4-hydroxy-2-methylcyclohexyl)-3-(p-hydroxyphenyl)urea, l-(4-hydroxy-2-... 

Match and mismatch of chiral catalyst with chiral substrate are distinctive, that is, matched combination generally brings high yield and high stereocontrol/regiocontrol. For example, treatment of (lS,2/ )-cij-2-methylcyclohexyl diazoacetate with Rh2(4/f-MPPIM)4 resulted virtually completely in the production of the all-cix bicyclic insertion product of Scheme 5.8... 

The stereoelectronic requirements of groups undergoing base-promoted elimination is also easily seen by stereochemical studies. Treatment of trans-2-methylcyclohexyl tosylate gives 3-methylcyclohexene as the major product while treatment of czs-2-methylcyclohexyl tosylate gives the more stable 1-methylcyclohexene as tire only product. 

The reaction is sensitive to the size of R thus no ketone was obtained from bis(2-methylcyclohexyl)hexylborane. 

Challenge Organic (CH2C12) Diesel" O-Ethyl O-2-methylcyclohexyl 2.B.4... 

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