Radicals masquerading as electrophiles: dual orbital effects in nitrogen-philic acyl radical cyclization and related addition reactions.
Free-radical chemistry has come a long way in a relatively short period of time. The synthetic practitioner takes for granted the wealth of mechanistic and rate constant data now available and can apply free-radical techniques to the synthesis of many different classes of target molecule with confidence. Despite this, there are still mechanistic anomalies that need to be addressed. This Account highlights recent work involving nucleophilic radicals with low-lying unoccupied orbitals, such as acyl, oxyacyl, silyl, stannyl, and germyl radicals. Through interesting singly occupied molecular orbital (SOMO)-pi* and highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) interactions during these reactions, the radicals involved are able to mask as electrophiles, providing high levels of regiocontrol and efficient methods for the synthesis of important heterocycles.
Schiesser
Carl H
CH
School of Chemistry, The University of Melbourne, Victoria, Australia.
Wille
Uta
U
Matsubara
Hiroshi
H
Ryu
Ilhyong
I
D000215:Acylation; D002244:Carbon / Q000737:chemistry; D003500:Cyclization; D005609:Free Radicals / Q000737:chemistry*; D005857:Germanium / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D007097:Imines / Q000737:chemistry; D008956:Models, Chemical; D008958:Models, Molecular; D009584:Nitrogen / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis*; D011083:Polycyclic Compounds / Q000138:chemical synthesis*; D012825:Silicon / Q000737:chemistry; D013816:Thermodynamics; D014001:Tin / Q000737:chemistry; D014753:Vinyl Compounds / Q000737:chemistry
D005609:Free Radicals; D006571:Heterocyclic Compounds; D007097:Imines; D009942:Organometallic Compounds; D011083:Polycyclic Compounds; D014753:Vinyl Compounds; D005857:Germanium; D014001:Tin; D002244:Carbon; D009584:Nitrogen; D012825:Silicon