Organolithium-induced enantioselective alkylative double ring-opening of epoxides: synthesis of enantioenriched unsaturated amino alcohols

Reductive Alkylation of β-Alkoxy Aziridines: New Route to Substituted Allylic Amines

[reaction: see text] A new route to substituted cyclic allylic amines via the reductive alkylation of beta-alkoxy aziridines using excess alkyllithium reagents is described.

Synthesis ofd- andl-2,3-trans-3,4-cis-4,5-trans-3,4-Dihydroxy-5-hydroxymethylproline and Tripeptides Containing Them

Enantiomerically pure (-)-(1R,4R,5R,6S)- and (+)-(1S,4S,5S,6R)-7-(tert-butoxycarbonyl)-5,6-exo-isopropylidenedioxy-7-azabicyclo[2.2.1]hept-2-one ((-)-3 and (+)-3) have been obtained from the Diels-Alder adduct of N-(tert-butoxycarbonyl)pyrrole and 2-bromo-1-(p-toluenesulfonyl)acetylene, including the Alexakis optical resolution of ketone (+/-)-3 via formation of cyclic aminals with (1R,2R)-diphenylethylenediamine. Compounds (-)-3 and (+)-3 were converted into d- and l-2,3-trans-3,4-cis-4,5-trans-N-(tert-butoxycarbonyl)-5-hydroxymethyl-3,4-isopropylidenedioxyprolines (-)-4 and (+)-4, respectively. Applying the Boc and Fmoc strategies of peptide synthesis, these compounds were used to construct two tripeptides containing the d- or l-2,3-trans-3,4-cis-4,5-trans-3,4-dihydroxy-5-hydroxymethylproline.

Unsaturated 1,2-amino alcohols and ethers from aziridines and organolithiums

Organolithium-induced ring-opening of aziridines of 2,5-dihydrofuran (5 and 8) and 1,4-dimethoxybut-2-ene (16, 17 and 23) gives 3-substituted 2-aminobut-3-en-1-ols 9-15 and amino ethers 18-20 and 24-26.