Asymmetric Synthesis of Heterocyclic Chloroamines and Aziridines by Enantioselective Protonation of Catalytically Generated Enamines**

Abstract

We report a method for the synthesis of chiral vicinal chloroamines via asymmetric protonation of catalytically generated prochiral chloroenamines using chiral Brønsted acids. The process is highly enantioselective, with the origin of asymmetry and catalyst substituent effects [a] Dr.

Enantioselective 1,3-Dipolar Cycloaddition Using (Z)-α-Amidonitroalkenes as a Key Step to the Access to Chiral cis-3,4-Diaminopyrrolidines

“…Cu(OTf) 0 --14 4 Cu(OTf) 2 0 --1 Conversion was determined by analysis of the 1 H NMR spectra of the crude compound. 2 The ratio was determined by analysis of the 1 H NMR spectra of the crude compound. 3 Determined by HPLC analysis using chiral stationary phase columns for the major endo-9ba diastereoisomer.…”

“…Currently, there is no unified approach to synthesize these chiral vicinal diamines, and they are often challenging to obtain, especially if unsymmetrically substituted. Recent studies dealt with the protonation of enamines [ 2 ], borylcopper-mediated homocouplins [ 3 ], diaza-Cope rearrangements [ 4 ], transformations of diols [ 5 ] and mefloquine [ 6 ], metal catalysis [ 7 , 8 , 9 ], Mannich reactions [ 10 ], nucleophilic trifluoromethylation [ 11 , 12 ], enantioselective reductive coupling of imines [ 13 , 14 ], syn -diamination of alkenes [ 15 ], etc.…”

“…The ratio was determined by analysis of the 1 H NMR spectra of the crude compound 2. Chemical yields isolated after flash chromatography 3.…”

Recent advances in the accessibility, synthetic utility, and biological applications of aziridines

“…The aziridine ring ( 13) is achieved after treating the so-formed α-chloroamine 12 with a base in a one-pot process (Scheme 3). 8 Catalysis is one of the most used methodologies for preparing aziridine derivatives. Indeed, a lot of pathways have been described by using different catalysts.…”

“…The aziridine ring ( 13 ) is achieved after treating the so-formed α-chloroamine 12 with a base in a one-pot process (Scheme 3). 8…”