Lipshutz reagent

How does this reaction, that is, formation of the Z-dienoaldehyde, occur Treatment of the D-mamo-demed allylic mesylate 75 with the Lipshutz reagent ( Bu3SnCu ) afforded the secondary allyltin 76 as the predominant product [53] small amounts (< 1 %) of the epimer at the C-6 was also formed (Figure 10.23). We proved that thermal rearrangement of the secondary sugar allyltins proceeded via the concerted mechanism as shown in Figure 10.23 [41, 54]. 

See Stemmier, T.L. Barnhart, T.M. Penner-Hahn, J.E. Tucker, C.E. Knochel, P. Bohme, M. Frenklng, G. J. Am. Chem. Soc., 1995, 117, 12489 for a discussion concerning the structure of organocuprate reagents. Solution compositions of Gilman reagents have also been studied. See Lipshutz, B.H. Kayser, F. Siegmann, K. Tetrahedron Lett., 1993, 34, 6693. 

Though organocopper reagents such as Gilman-type or Lipshutz-type reagents have been widely used to date, there have been only a few reports concerning the catalytic use of a copper source. 

The importance of cyanocuprates as a synthetic tool in organic chemistry is well established. Depending on the amount of organolithium reagent LiR (one or two equivalents) added to CuCN, two different type of cyanocuprates are formed, with stoichiometries of RCu(CN)Li and R2Cu(CN)Li2, respectively [122] (Scheme 1.23). In order to distinguish between these two different types of cyanocuprates, the term higher-order cyanocuprates was introduced by Lipshutz et. al. for the second type of cyanocuprate, and the term lower-order cyanocuprate consequently... 

Transmetalation reactions of organozirconium reagents were pioneered by Schwartz [130-132], with improved procedures developed more recently by Lipshutz [133] and Wipf [134]. The hydrozirconation of 1-hexene with H(Cl)ZrCp2 at 25 °C under sonication conditions produces the n-hexylzirconium complex 127, which adds to cyclohexenone in the presence of CuBr-Me2S (10 mol%) to afford the desired product 128 in 79% isolated yield (Scheme 2.61) [134]. 

R. J. K. Taylor (Ed.), Organocopper Reagents, Oxford University Press, Oxford, 1994 m) B. H. Lipshutz in Organometallics in Synthesis, ScHLOSSER, M. (ed.), Wiley,... 

For a method of preparing this reagent (which is also available commercially), sec Buchwald LaMaire Nielsen Watson King Tetrahedron Lett. 1987,28, 3895. It can also be generated in situ Lipshutz Keil Ellsworth Tetrahedron Lett. 1990,3/, 7257. 

B. H. Lipshutz and S. Sengupta, Organocopper reagents Substitution, conjugate addition, carbo/metallocupration and other reactions, Org. React. 41 135 (1992). 

Lipshutz, B. H. Hackmann, C. Conjugate addition reactions of allylic copper species derived from Grignard reagents synthetic and spectroscopic aspects./. Org. Chem. 1994, 59, 7437-7444. 

B. H. Lipshutz, S. Sengupta, Organocopper Reagents Substitution, Conjugate Addition, Carbo/Metal-locupration, and Other Reactions, Org. React. 1992, 41, 135-631. 

B. H. Lipshutz, Organocopper Reagents, in Comprehensive Organic Synthesis (B. M. Trost, I. Fleming, Eds.), Vol. 1, 107, Pergamon Press, Oxford, 1991. 

B. H. Lipshutz, Synthetic Procedures Involving Organocopper Reagents, in Organometallics. A Manual (M. Schlosser, Ed.), 283, Wiley, Chichester, 1994. 

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