Simple Synthetic Equivalents for the β-(N,N-Disubstituted)ethylamino Acyl Cation Synthon and their Applications

Abstract

Various N,N-disubstituted-β-amino-N-methoxy-N-methylpropanamides 3a-i were prepared which served as an excellent β-aminoacyl cation equivalents. These were used to prepare β-amino ketones 1, pharmacologically active tertiary 1-(3,3-diarylpropyl)amines 7a-c, and the interesting C-glycoside 8.

Keywords

Weinreb amide - β-amino ketones - Grignard reactions - alkylations - glycoside

References

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  Compound 3c was prepared by refluxing a mixture of benzylamine (1 g, 9.33 mmol) and veratraldehyde (1.55 g, 9.33 mmol) in benzene (10 mL) for 2 h. The solvent was evaporated and dissolved in anhyd EtOH (8 mL), treated with NaBH₄ (0.68 g, 18 mmol) at 0 °C for 1 h to afford 3c as a colourless oil in quantitative yield (2.5 g, 96%). The product was directly used for further alkylation.

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