Oxidations 1 -methoxy-2-methyl-1 - propene

The effect of chain length on the catalytic performance was investigated using a series of co-bromo-2-methylalkenes. In all cases the predominant enantiomer produced had the -configuration except for 3-bromo-2-methylpropene oxide, which was predominantly in the S-form due to the priority switch [274], The short propene and butene derivatives were converted quantitatively whereas the longer pentene, hexene and heptene substrates failed to convert completely. Many other functional groups such as carboxylic ester, methoxy, acetoxy and carbonic ester are accepted by the system. The epoxidation fails, however, for 4-hydroxy-2-methyl-l-butene as substrate [270]. 

In order to probe this phenomenon quantitatively in an uncharged system where solvation effects are known to be relatively unimportant, the rates of cycloadditions of two relatively electron-deficient 1,3-dipoles, p-methoxy and p-nitro benzonitrile oxides (MBNO and NMBO, respectively) to a series of simple alkenes — propene, 1-butene, 1-pentene, 1-hexene, 3-methyl-l-butene, 3,3-dimethyl-l-butene and isobutene — were measured70. In each of these reactions, only the 5-alkyl-3-aryliso-xazolines were formed. 

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