Reactions of nitrogen compounds with ruthenium tetroxide. Determination of the absolute configuration of 3‐ethylpiperidine

Abstract

(‐)‐3‐Kthylpiperidine and (R)‐(‐)‐2‐ethylglutarie acid have been chemically correlated through N‐subslituted α‐ethylglutarimides obtained from the oxidation of optically active N‐ethyl‐ and N‐benzyl‐3‐ethylpiperidine with ruthenium tetroxide. The (R)‐(‐) configuration of (‐)‐3‐ethylpiperidine was confirmed by CD measurements. The selective oxidation of endocyclic methylenes linked to the nitrogen atom was explained in term of different conformational freedom of endo‐ and exocyclic methylene groups.

Asymmetric synthesis of 2-arylpyrrolidines starting from γ-chloro N-(tert-butanesulfinyl)ketimines

“…1.1 equiv. of LiBEt 3 H, THF, À78 1C, 1 h then rt, 14-20 h, the enantiomeric (S S )-N- 15,17,18 The absolute configuration of 2-arylpyrrolidines can also easily be determined by inspection of the multiplicity of the NMR signal of the methine proton of the pyrrolidine ring in the corresponding Mosher's amides. 19,20 2-Phenylpyrrolidines (S)-5a and (R)-5a were reacted with 2.5 equiv.…”

Oxidations of Amines, Amides, Ethers, Sulfides, Phosphines, Arsines, Stibines and Miscellaneous Substrates

“…In a competitive reaction with a primary alcohol (1-undecanol), hydroxylamine was preferentially oxidised to the corresponding nitrone, giving a >50:1 reaction rate of amine to alcohol [29] [36,37]. N-protected secondary amines were oxidised by electrogenerated RuO 4 from RuO 2 /aq.…”

The Oxidation of Amides to Imides: A Powerful Synthetic Transformation

“…38 Due to the excellent compatibility of the ruthenium tetroxide oxidation with chiral lactam substrates, it can also be used as a degradation tool to determine the unknown stereochemistry of lactams by oxidation then hydrolysis to the known amino acid. 39…”