Rapid Asymmetric Synthesis of Disubstituted Allenes by Coupling of Flow-Generated Diazo Compounds and Propargylated Amines.
We report herein the asymmetric coupling of flow-generated unstabilized diazo compounds and propargylated amine derivatives, using a new pyridinebis(imidazoline) ligand, a copper catalyst and base. The reaction proceeds rapidly, generating chiral allenes in 10-20 minutes with high enantioselectivity (89-98 % de/ee), moderate yields and a wide functional group tolerance.
['Poh|Jian-Siang|JS|0000-0002-6173-8290', 'Makai|Szabolcs|S|', 'von Keutz|Timo|T|', 'Tran|Duc N|DN|0000-0001-7864-2730', 'Battilocchio|Claudio|C|0000-0002-4601-8527', 'Pasau|Patrick|P|', 'Ley|Steven V|SV|0000-0002-7816-0042']
allenes diazo compounds copper asymmetric catalysis flow chemistry