3-Methyl-5-phenyloxazolidine and naphtho[1,2-e][1,3]oxazine
were successfully involved in the developed process to form α-
aminonitriles 4k and 4l, respectively, in good overall yields.
leads to the complete absence of selectivity in the observed
reaction.
Table 2. Synthesis of aminoacetonitriles 4.a
Scheme 4. Dealkylation of salt 5.
In summary, we report a new method for the functionalization
of various N-methylazaheterocycles by substitution of the methyl
group by a cyanomethyl moiety. The proposed strategy is based
on the selective demethylation of readily available quaternary
ammonium salts of starting amines under the simple conditions.
In view of the broad possibilities for the 1,3-dipolar
cycloaddition of azomethine ylides in obtaining various N-
methylazaheterocycles, this concept allows easy access to a wide
range of α-aminonitriles and is expected to find application in the
synthesis and the modification of natural and pharmaceutical
compounds. Further investigation of the aminoacetonitriles is
underway in our laboratory and will be reported in due course.
Acknowledgments
This work was financially supported by the Russian Science
Foundation (Grant 17-73-20070). We also thank Sergey Usachev
for his remarks.
References and notes
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