- Chemical and Spectroscopic Observations on the Properties and Composition of Higher Order, Mixed Organocuprates, R2Cu(CN)Li2
-
The nature of organocuprates of general formula R2Cu(CN)Li2, derived from CuCN and 2RLi, is described in terms of their structural integrity in solution.A combination of chemical and spectroscopic tests conclusively demonstrates facile dissociation-reassociation of alkyl groups on copper.Data derived from both IR and variable temperature NMR spectra suggest that different aggregation states between Et2O and THF based solutions of these reagents exist.
- Lipshutz, Bruce H.,Kozlowski, Joseph A.,Wilhelm, Robert S.
-
-
Read Online
- REACTION OF ETHYLMAGNESIUM BROMIDE WITH CARBOXYLIC ESTERS IN THE PRESENCE OF TRIBUTYL VANADATE
-
The reaction of the butyl esters of carboxylic acids with an excess of ethylmagnesium bromide in the presence of catalytic amounts of tributyl vanadate leads to 1-substituted 1-cyclopropanols with yields of 41-83percent.
- Kulinkovich, O. G.,Sorokin, V. L.,Kel'in, A. V.
-
-
- Substitution Reactions of Secondary Halides and Epoxides with Higher Order, Mixed Organocuprates, R2Cu(CN)Li2: Synthetic, Stereochemical, and Mechanistic Aspects
-
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.
- Lipshutz, Bruce H.,Wilhelm, Robert S.,Kozlowski, Joseph A.,Parker, David
-
p. 3928 - 3938
(2007/10/02)
-