Copper phosphoramidite-catalyzed enantioselective desymmetrization of meso-cyclic allylic bisdiethyl phosphates.
[reaction: see text] A highly regio-, diastereo-, and enantioselective desymmetrization of five-, six-, and seven-membered meso-cyclic allylic bis-diethyl phosphates (2a, 2b, and 2c, respectively) was obtained with diethylzinc, using catalytic amounts of [Cu(OTf)](2).C(6)H(6) and phosphoramidite ligands 5. Enantiomeric excesses of up to 87, 94, and >98% were obtained for the addition of diethylzinc to cyclopentene, cyclohexene, and cycloheptene bis-diethyl phosphates, respectively.
Dipartimento di Scienze Chimiche, Fisiche e Matematiche, Università dell'Insubria, via Valleggio 11, I- 22100 Como, Italy. umberto.piraulli@uninsubria.it
Umberto
U
Piarulli
Christelle
C
Claverie
Philippe
P
Daubos
Cesare
C
Gennari
Adriaan J
AJ
Minnaard
Ben L
BL
Feringa