Direct Conversion of Primary Alcohols to 1,2-Amino Alcohols: Enantioselective Iridium-Catalyzed Carbonyl Reductive Coupling of Phthalimido-Allene via Hydrogen Auto-Transfer

The first catalytic enantio­selective
carbonyl (α-amino)­allylations
are described. Phthalimido-allene 1 and primary alcohols 2a–2z, 2a′–2c′ engage in hydrogen auto-transfer-mediated carbonyl
reductive coupling by way of (α-amino)­allyliridium−aldehyde
pairs to form vicinal amino alcohols 3a–3z, 3a′–3c′ with high levels of regio-, anti-diastereo-, and
enantio­selectivity. Reaction progress kinetic analysis and isotopic
labeling studies corroborate a catalytic cycle involving turnover-limiting
alcohol dehydrogenation followed by rapid allene hydrometalation.