Direct
Conversion of Primary Alcohols to 1,2-Amino
Alcohols: Enantioselective Iridium-Catalyzed Carbonyl Reductive Coupling
of Phthalimido-Allene via Hydrogen Auto-Transfer
posted on 2019-08-29, 14:05authored byKim Spielmann, Ming Xiang, Leyah A. Schwartz, Michael J. Krische
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.