Organocopper 1,4-addition

For addition reactions involving vinylic copper reagents derived from organocopper additions to alkynes, see page 452, Section 2.28. 

Organocopper Addition (Alkene to -Functionalized Product). Tri-n-butylphosphine-stabilized organocopper reagents add in a conjugate fashion to trans-cnoaic derivatives of the 10-dicyclohexylsulfonamidoisobomeol auxiliary from the less hindered C(a)-s ( r-face with excellent selectivity (eq 2) (Table 1). This type of reaction has formed the basis of several natural product syntheses. ... 

Xiang, J. and Fuchs, P. L. 1996. AUcenylation of C-H bonds via reaction with vinyl and dienyl triflones. Stereospecific synthesis of trisubstituted vinyl triflones via organocopper addition to acetylenic triflones. J. Am. Chem. Soc. 118 11986-11987. 

CONJUGATE ADDITION OF ORGANOCOPPER REAGENTS TO a,p-UNSATURATED CARBONYL COMPOUNDS... 

Michael additions [112] and other reactions typical of organocopper species can also be performed witli silylcoppet reagents such as TBDMSCu, prepared by Sn/Cu exchange [113] between Me- SnSiMeyifBu) and BuiHi)CuLi-LiCN iHi = 2-tbienyl) iScbeme 2.53) [113, 114]. 

Witli tlie reagent PbCu in tlie presence of tlie additives BF and PBu- , ees of up to 9 596 were obtained, wb de values of up to 8 596 were acliievable witli a vinyl copper reagent. Chiral dienic acetals have also been studied tliree regioisomeric products could be obtained in tliis case as tlie result of Su2, Su2, or Su2" attaclt of tlie organocopper reagent [25]. Mixtures were indeed obtained witli alKyl copper reagents, but PbCu-BF resulted in fotniation of only tlie S 2 and Su2" products, witli selectivity for tlie latter fSclieme 8.12). 

Conjugale addition of organocopper r niLiltifiinctional groups in tlie bnal carl niLinosuppressant FK-506 i25) [17] was n... 

Organocopper chemistry is still rapidly expanding its syntlietic scope. Hie scope of carbocupration, previously limited to acetylenes, has recently been extended to olefins [33-36]. 1,6-, 1,8-, 1,10-, and 1,12-Addition and 1,5-Su2" substitution reac-... 

Conjugate Addition of Alkyl Groups Organocopper Reactions... 

With respect to the nucleophilic addition of organocopper reagents, a sharp contrast between the rigid isopropylidene glyceraldehyde and its open-chained analog, 2,3-bis(benzyloxy)propanal. was observed (compare Tables 15 and 16). With the isopropylidene-protected aldehyde a high syn diastereoselectivity could only be obtained when tetrahydrofuran was used as reaction solvent, and the diastereoselectivity dropped considerably in diethyl ether. In contrast, the latter solvent allows excellent syn selectivities in additions to the dibenzyl-protected glyceraldehyde81. On the other hand, tetrahydrofuran yields better results than diethyl ether in the... 

The relative reactivity of organocopper compounds in additions to 6 and 7 is as follows vinyl > aryl > isopropyl > ethyl > methyl. 

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