Methyl-2-propoxide

Sodium 2-Methyl-2-propoxide, see Sodium fert-butoxide, 1661b... 

Methyl-2-propanol Potassium Potassium 2-methyl-2-propoxide... 

Outline a complete mechanistic sequence for the reaction of 2-bromobutane with potassium 2-methyl-2-propoxide in 2-methyl-2-propanol solvent to form the three alkenes generated in the reaction (1-butene, fra s-2-butene, and cis-2-butene). Include a clear drawing of the anti-periplanar transition state for the formation of each alkene. 

TABLE 7.12. A Comparison of the Yields of Hexenes Obtained from 2-Halohexanes as a Function of Leaving Group (Halogen) vrith t-Bntoxide (2-Methyl-2-Propoxide [(CH3)3C0 ]> in Methylsnilinylmethane (Dimethyl Sulfoxide [(CH3)2SO])... 

Now, consider the diastereomeric erythro- and t/treo-5-chloro-6-deuteriodecanes shown in Schemes 7.36 and 7.37, respectively. As shown, when these diastereomers are, individually, treated with with f-butoxide (2-methyl-2-propoxide [(CHajaCO j)... 

Scheme 7.37. The results of E2 elimination of HCl and HCI fromf/ire<7-5-chloro-6-deuterio-decane with f-butoxide (2-methyl-2-propoxide [(CH3)3C0 ]) in methylsuUmyhnethane (dimethyl sulfoxide, DMSO [(CH3)2SO]) solvent. Note that syn-elimination provides ( )-alkene that has lost deuterium ( H) and (Z)-alkene that has lost protium ( H).Thus,examination of the separated alkenes by mass spectroscopy provides definitive information about the path, and the results must be complementary to those in Scheme 7.36. (See Scheme 7.36 for reference information).

Figure 7.30. (Z)- and ( )- (or cis and trans) 4-bromo-(l,l-dimethylethyl)-cyclohexane (4-bromo-f-butylcyclohexane), Both undergo E2 elimination with f-butoxide (2-methyl-2-propoxide [(CH3)3CO ]) in f-butanol (2-methyl-2-propanol [(CH3)3COH]), The (Z)-isomer, with the bromine axial and two anticoplanar protons, reacts about 500 times faster than its...

The indirect deactivation in 2-amino-4-chloroquinoline (187) requires vigorous conditions (potassium hydroxide in hot ethylene glycol, or boiling propanolic propoxide for 16 hr) to displace the chloro group, which is stable to aqueous alkali and to hydriodic acid. The direct deactivation in 5-amino-2-chloro-3-cyano-6-methyl-pyridine (188) prevents reaction with alkoxide ion under conditions which produce smooth reaction of the des-amino analog. 

Treatment of methyl 4-0-ethyl-3-0-methyl-/3-D-threo-pento-sidulose (70), a model compound having a carbonyl group at C-2, with sodium 1-propoxide in 1-propanol resulted131 in quantitative elimination of ethanol and the formation of methyl 4-deoxy-3-0-methylpent-3-enosid-2-ulose (71). On further mild hydrolysis of this and related compounds, the substituents at C-l and C-3 were released (see Scheme 10).132... 

Diazomethane (rs, 3 Ciazomethane and its homologs are prq>ared by the action of sodium fju-propoxide in wo-propyl alcohol upon the products of nitrosation from /9-alkylamino-iso-butyl methyl ketones (obtained by adding the amine to mesityl oxide). Adamson and Kenner, J. Chem. Soc. 1935, 286. 

The most extensive application of the Oppenauer oxidation has been in the oxidation of steroid molecules. The most common aluminum catalysts are aluminum /-butoxide, i-propoxide, and phenoxide. While only catalytic amounts of the aluminum alkoxide are theoretically required, in practice at least 0.25 mole of alkoxide per mole of alcohol is used. Acetone and methyl ethyl ketone have proved valuable hydride acceptors due to their accessibility and ease of separation from the product, whereas other ketones such as cyclohexanone and p-benzoquinone are useful alternatives, due to their increased oxidation potentials.4 Although the reaction can be performed neat, an inert solvent to dilute the reaction mixture can reduce the extent of condensation, and, as such, benzene, toluene, and dioxane are commonly utilized. Oxidation of the substrate takes place at temperatures ranging from room temperature to reflux, with reaction times varying from fifteen minutes to twenty-four hours and yields ranging from 37% to 95%. 

The methyl iodides of dimethyl hydrazones furnish 2 -azirines when treated with bases such as sodium propoxide ... 

HF calculations of the structures and vibrational frequencies of monomers and dimers of lithium alkyl carbonates (methyl, ethyl, and propyl carbonate lithium) and lithium alkoxides (lithium methoxide, lithium ethoxide, lithium propoxide, and lithium butoxide) indicate that they adopt dimeric structures. Dimerisation energies of 214 kJ mol for lithium alkyl carbonates and 266 kJ mol for lithium alkoxides are calculated and are found to be approximately independent of the chain length. 

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