title: Anionic access to silylated and germylated binuclear heterocycles.
abstract: A simple access to silylated and germylated binuclear heterocycles, based on an original anionic rearrangement, is described. A set of electron-rich and electron-poor silylated aromatic and heteroaromatic substrates were tested to understand the mechanism and the factors controlling this rearrangement, in particular its regioselectivity. This parameter was shown to follow the rules proposed before from a few examples. Then, the effect of the substituents borne by the silicon itself, in particular the selectivity of the ligand transfer, was studied. Additionally, this chemistry was extended to germylated substrates. A hypervalent germanium species, comparable to the putative intermediate proposed with silicon, seems to be involved. However, a pathway implicating the elimination of LiCH2Cl was observed for the first time with this element, leading to unexpected products of the benzo-oxa (or benzo-aza) germol-type.
authors.affiliation: Laboratoire COBRA, CNRS UMR 6014 & FR 3038, Université de Rouen and INSA de Rouen, 76821, Mont St Aignan Cedex (France), Fax: (+33) 235-522-971; Current address: Organic Chemistry P3A Group, ICMMO, CNRS UMR 8182, Université Paris-Sud, 15 rue Georges Clemenceau, 91405 Orsay cedex (France).
authors.forename: Thomas
authors.initials: T
authors.lastname: Boddaert
authors.forename: Cyril
authors.initials: C
authors.lastname: François
authors.forename: Laetitia
authors.initials: L
authors.lastname: Mistico
authors.forename: Olivier
authors.initials: O
authors.lastname: Querolle
authors.forename: Lieven
authors.initials: L
authors.lastname: Meerpoel
authors.forename: Patrick
authors.initials: P
authors.lastname: Angibaud
authors.forename: Muriel
authors.initials: M
authors.lastname: Durandetti
authors.forename: Jacques
authors.initials: J
authors.lastname: Maddaluno
mesh_terms: D000838:Anions / Q000737:chemistry*; D003500:Cyclization; D005857:Germanium / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry; D012821:Silanes / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000838:Anions; D006571:Heterocyclic Compounds; D012821:Silanes; D005857:Germanium; D008094:Lithium
keywords: cyclization; heterocycles; lithium; reaction mechanisms; rearrangement