The first examples of highly enantioselective Narasaka-Heck cyclizations are described. A SPINOL-derived P,N-ligand system enables Pd-catalyzed 5-exo cyclization of a range of oxime esters with sterically diverse trisubstituted alkenes to generate dihydropyrroles containing tetrasubstituted nitrogen-bearing stereocenters in 56 to 86% yield and 90 : 10 to 95 : 5 e.r. These processes are rare examples of reactions that proceed via enantioselective migratory insertion of alkenes into Pd-N bonds, and the first where trisubstituted alkenes are used to generate tetrasubstituted stereocenters with high enantioselectivity.
Bibliographical noteFunding Information:
We thank the EPSRC (EP/J007455/1) and the European Research Council (ERC grant 639594 CatHet) for financial support. A. F. thanks AstraZeneca and N. J. R. thanks the Bristol Chemical Synthesis Doctoral Training Centre, funded by the EPSRC (EP/G036764/1), for a Ph.D. studentship. N. J. R. thanks the SCI for a postgraduate scholarship. J. F. B. is indebted to the Royal Society for a University Research Fellowship.
© The Royal Society of Chemistry.