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Radical-mediated controllable difunctionalization of alkenes provides a powerful tool for the manipulation of olefins and has become a hot topic recently. In general, however, the scope of alkene is largely restricted to the activated alkenes. The development of a general strategy for the functionalization of unactivated alkenes is desired, yet remains challenging. In this review, we have summarized the recent advances in the strategy of intramolecularly distal migration of functional groups which has been efficiently applied in the radical-mediated difunctionalization of unactivated alkenes. A portfolio of functionalities including aryl, cyano, heteroaryl, imino, carbonyl, alkynyl, and alkenyl groups showcase the migratory aptitude. [ABSTRACT FROM AUTHOR]

A Ru-catalyzed olefin migration reaction of chiral cyclic allylic acetal is reported. The reaction generates cyclic enol acetal in a highly chemoselective manner. A variety of O,O- and N,O-acetals participated in the reaction with conservation of the stereochemical integrity of the acetal moiety. The utility of the reaction was demonstrated by the short and protective group-free syntheses of (L)-deoxyribonucleoside and β-amicetose glycoside. [ABSTRACT FROM AUTHOR]

A simple and efficient method for Cp*CoIII-catalyzed C-H bond alkylation using activated olefins was developed. Selective C-H monoalkylation was performed at ambient temperature. One-pot symmetrical dialkylation and sequential unsymmetrical C-H dialkylation were performed to give the desired products in excellent yields. The reaction was found to proceed through an M-alkyl intermediate after migratory insertion, and this intermediate undergoes protodemetalation to give the expected alkylated product along with the regenerated catalyst. [ABSTRACT FROM AUTHOR]

A simple and efficient method for Cp*CoIII-catalyzed C-H bond alkylation using activated olefins was developed. Selective C-H monoalkylation was performed at ambient temperature. One-pot symmetrical dialkylation and sequential unsymmetrical C-H dialkylation were performed to give the desired products in excellent yields. The reaction was found to proceed through an M-alkyl intermediate after migratory insertion, and this intermediate undergoes protodemetalation to give the expected alkylated product along with the regenerated catalyst. [ABSTRACT FROM AUTHOR]

In this work we show that classic coordination of the oxo group in an oxorhenium hydride complex to M(C6F5)3 (M = Al, B) leads to dramatic increases in the rate of migratory olefin insertion. Combined experimental and computational studies have been utilized to understand the reasons for the rate enhancement upon coordination of the oxo group to the Lewis acid. The mechanism for migratory insertion involves coordination of the olefin to rhenium in the equatorial plane. This induces mixing of the rhenium--hydride σ bond with a rhenium-oxygen π* orbital. This results in an accumulation of electron density on the oxo ligand. The Lewis acid lowers the barrier for migratory insertion by diminishing the electron density on the oxo ligand in the transition state. [ABSTRACT FROM AUTHOR]

Herein we report a novel, general protocol for distal heteroaryl ipso-migration and its application to the elusive heteroarylation of unactivated alkenes. A set of nitrogen-containing heteroaryl groups showcase the migratory aptitude. This reaction provides a variety of fluoroalkyl functionalized heteroarenes under mild reaction conditions. This is the first report of a difunctionalization of unactivated alkenes with distal heteroaryl migration. [ABSTRACT FROM AUTHOR]

Cobalt boryl complexes, which have only been sporadically reported, can be accessed systematically with remarkable (but controllable) variation in the nature of the MB bond. Complexes incorporating a very strong trans σ-donor display unparalleled inertness, reflected in retention of the MB bond even in the presence of extremely strong acid. By contrast, the use of the strong π-acceptor CO in the trans position, results in significant CoB elongation and to labilization of the boryl ligand via unprecedented CO migratory insertion. Such chemistry provides a pathway for the generation of coordinative unsaturation, thereby enabling ligand substitution and/or substrate assimilation. Alkene functionalization by boryl transfer, a well-known reaction for noble metals such as Rh or Pt, can thus be effected by an 18-electron base-metal complex. [ABSTRACT FROM AUTHOR]

A metal-free and cost-effective synthetic protocol for selective aryltrifluoromethylation of allylic alcohols with Langlois' reagent (CF3SO2Na) through cascade trifluoromethyl radical addition/1,2-aryl migration has been developed. The highlights of this procedure are operational simplicity, excellent functional group tolerance, and mild reaction conditions. [ABSTRACT FROM AUTHOR]

Getting your bonds in a twist: Selective transition metal‐catalyzed isomerization and migration of double bonds in alkenes and 1,3‐dienes are attracting increasing attention. The recent advances in this field exhibit inspiring new perspectives for applications of such reactions in the future. [ABSTRACT FROM AUTHOR]