title: Preparation of stereodefined secondary alkyllithium compounds.
abstract: We have developed a practical stereoretentive iodine/lithium-exchange process that allows the stereodefined preparation of cis- and trans-cycloalkyllithium compounds from their corresponding stereodefined iodides. Quenching with electrophiles offers stereospecific access to both cis- (up to 96% cis) and trans-cycloalkyl derivatives (up to 99% trans). A detailed study of the thermodynamic stabilities, stereochemical behavior, and reactivities of axially and equatorially substituted cyclohexyllithium reagents is reported. Ab initio calculations demonstrate that the formation of oligomeric cyclohexyllithium structures is pivotal for explaining the observed stereochemical preference.
authors: Department Chemie, Ludwig-Maximilian-Universität München, Butenandtstrasse 5-13, Haus F, 81377 München, Germany.
authors: Stephanie
authors: S
authors: Seel
authors: Guillaume
authors: G
authors: Dagousset
authors: Tobias
authors: T
authors: Thaler
authors: Annette
authors: A
authors: Frischmuth
authors: Konstantin
authors: K
authors: Karaghiosoff
authors: Hendrik
authors: H
authors: Zipse
authors: Paul
authors: P
authors: Knochel
mesh_terms: D007455:Iodine / Q000737:chemistry; D008094:Lithium / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D009942:Organometallic Compounds; D007455:Iodine; D008094:Lithium