111016-17-2Relevant academic research and scientific papers
X=Y-ZH SYSTEMS AS POTENTIAL 1,3-DIPOLES. PART 12. MECHANISM OF FORMATION OF AZOMETHINE YLIDES VIA THE DECARBOXYLATIVE ROUTE FROM α-AMINO ACIDS
Grigg, Ronald,Idle, Jonathan,McMeekin, Peter,Surendrakumar, Sivagnanasundram,Vipond, David
, p. 2703 - 2714 (2007/10/02)
The effect of temperature, solvent, and type of aldehyde on the stereospecific or stereoselective formation of azomethine ylides by the decarboxylative condensation of aldehydes with three types of α-amino acids, (i) cyclic secondary α-amino acids, (ii) cyclic secondary α-amino acids with a benzylic carboxy group, and (iii) acyclic primary α-amino acids, has been studied.Stereospecific anti-dipole formation in (i) and temperature dependent stereoselective anti-dipole formation in (ii) and (iii) is inferred from the stereochemisry of cycloadducts of the azomethine ylides with N-methylmaleimide.These results are used to support a mechanistic scheme involving loss of carbon dioxide from intermediate oxazolidin-5-ones in a stereospecific cycloreversion reaction.
