Stereoselective Retentive Domino Transmetalations of Secondary Alkyllithium Compounds to Functionalized Secondary Alkylcopper Reagents.
Functionalized secondary alkyllithium reagents obtained by I/Li exchange from the corresponding secondary alkyl iodides undergo two successive transmetalations with Me3 SiCH2 ZnBr⋅LiBr and CuBr⋅2 LiCl⋅Me2 S to provide functionalized secondary alkylcopper compounds with high retention of configuration. These alkylcopper derivatives react further with electrophiles such as alkynyl esters, acid chlorides, allylic chlorides, ketals, ethylene oxide, and 3-iodocyclopentanone with high retention of configuration. A related sequence of transmetalations with MeMgI and LaCl3 ⋅2 LiCl allows a retentive addition of secondary alkyllithium reagents to acetone. The influence of the solvent on the configurational stability of secondary alkylzinc reagents is described.
Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 München (Germany) http://www.knochel.cup.uni-muenchen.de/
Kohei
K
Moriya
Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 München (Germany) http://www.knochel.cup.uni-muenchen.de/
Meike
M
Simon
Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 München (Germany) http://www.knochel.cup.uni-muenchen.de/
Rasmus
R
Mose
Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 München (Germany) http://www.knochel.cup.uni-muenchen.de/
Konstantin
K
Karaghiosoff
Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 München (Germany) http://www.knochel.cup.uni-muenchen.de/. knoch@cup.uni-muenchen.de.
Paul
P
Knochel
configurational stability; copper; diastereoselectivity; lithium; zinc