The first catalytic asymmetric addition of TosMIC to unactivated ketones is presented. A combination of Me2Zn and aminoalcohol catalyst promoted the aldol addition/cyclization reaction to render oxazolines possessing a fully substituted stereocenter with excellent yields (up to 92 %), high enantioselectivities (up to 96 %), and complete diastereoselectivity. The chiral oxazolines were then used to give, after a straightforward acid hydrolysis, enantioenriched building blocks bearing tertiary alcohol motifs such as hydroxylaldehydes, hydroxylacids, and hydroxylesters without racemization.
Keeri, A.R., Gualandi, A., Mazzanti, A., Lewinski, J., Cozzi, P.G. (2015). Me2Zn-Mediated Catalytic Enantio- and Diastereoselective Addition of TosMIC to Ketones. CHEMISTRY-A EUROPEAN JOURNAL, 21(52), 18949-18952 [10.1002/chem.201504362].
Me2Zn-Mediated Catalytic Enantio- and Diastereoselective Addition of TosMIC to Ketones
KEERI, ABDUL RAHEEM;GUALANDI, ANDREA;MAZZANTI, ANDREA;COZZI, PIER GIORGIO
2015
Abstract
The first catalytic asymmetric addition of TosMIC to unactivated ketones is presented. A combination of Me2Zn and aminoalcohol catalyst promoted the aldol addition/cyclization reaction to render oxazolines possessing a fully substituted stereocenter with excellent yields (up to 92 %), high enantioselectivities (up to 96 %), and complete diastereoselectivity. The chiral oxazolines were then used to give, after a straightforward acid hydrolysis, enantioenriched building blocks bearing tertiary alcohol motifs such as hydroxylaldehydes, hydroxylacids, and hydroxylesters without racemization.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
