84370-47-8Relevant academic research and scientific papers
Substitution Reactions of Secondary Halides and Epoxides with Higher Order, Mixed Organocuprates, R2Cu(CN)Li2: Synthetic, Stereochemical, and Mechanistic Aspects
Lipshutz, Bruce H.,Wilhelm, Robert S.,Kozlowski, Joseph A.,Parker, David
, p. 3928 - 3938 (2007/10/02)
Higher order cuprates, represented by the general formula R2Cu(CN)Li2, are readily prepared from copper cyanide and 2 equiv of an organolithium.These novel reagents react readily and efficiently with secondary unactivated iodides and bromides affording products of substitution.Likewise, mono-, di-, and trisubstituted epoxides undergo ring opening leading to the corresponding alcohols in excellent yields.The effects of solvent, temperature, gegenion, and variations in ligands are discussed.Replacement of the second equivalent of RLi by CH3Li strongly encouragestransfer of R over CH3 in R(CH3)Cu(CN)Li2 with halides.Use of PhLi as RRLi in place of one RTLi (i.e.RT(Ph)Cu(CN)Li2) is suggested for oxirane cleavage.The stereochemical implications associated with both couplings are also addressed.
Chemistry of Higher Order, Mixed Organocuprates. 5. On the Choice of the Copper(I) Salt for the Formation of R2CuLi
Lipshutz, Bruce H.,Kozlowski, Joseph A.,Wilhelm, Robert S.
, p. 546 - 550 (2007/10/02)
Chemical and spectroscopic studies are presented that have been designed to manifest differences in reagent composition and reactivity between mixtures of CuI/2RLi and CuSCN/2RLi.The results indicate that while both Cu(I) salts are reported to serve as precursors to lower order cuprates R2CuLi, CuSCN may actually be forming a higher order, mixed species R2Cu(SCN)Li2.This would explain the discrepancy in coupling reactions of each solution with similar organic substrates under otherwise identical conditions.The presence of added lithium salts demonstrates that while Li I added to CuSCN/2RLi has essentially no effect, introduction of an equivalent of LiSCN to CuI/2RLi dramatically alters the efficiency of ligand transfer.
