Synthesis of the first kinetically stable dibenzosilafulvene

Abstract

The first stable dibenzosilafulvene, 9-{[8-(dimethylaminomethyl)-l-naphthyllphenylsil-1-ylium}fluoren-9-ide (Ta), was obtained in one step from 9-fluorenyllithium and chloro[8-(dimethylarninomethyl)-l-naphthyllphenylsilane as a stable solvate with THF. The structure of the zwitterionic compound 7a was established by IH, 13C, and 29Si NMR in solution and in the solid state. The reactions of compound 7a with crotonaldehyde, ethanol, and triethylethylidenephosphorane are described. 1"he data on the synthesis of alkoxy-and alkylthiochloro-9-fluorenylsilanes and their phosphortium salts are given.

Ab initio Study of Some Intramolecularly Donor‐Stabilized Silenes

“…[3][4][5][6] A particularly effective stabilization is expected, when substituents with donor groups are introduced to the silenes and intramolecular donor-acceptor interaction between this donor group and the electrophilic silicon center is possible. Such intramolecular NǞSi coordination was concluded from theoretical calculations of GuselЈnikov et al [7] for a 1-methylene-5-methyl-2,8-dioxa-5-aza-1-silacyclooctane, and a stable dibenzosilafulvene with an 8-dimethylaminomethyl-1-naphthyl group at the silicon atom was isolated by Chernyshev et al [8,9] However, no X-ray crystal structure analysis of the compound could be performed to validate their results.…”

Reaction of Dichloromethyltris(trimethylsilyl)silane with Organolithium Reagents: Synthesis of an Intramolecularly Donor-Stabilized Silene

“…The aforementioned clusters 1 a in the compound 1 a´% 150 H 2 O comprise Fe centers, with H 2 O ligands which become linked according to the inorganic-condensation reactions known for the formation of polycations with a low activation energies [3] (Scheme 1). The corresponding reaction product 2 results from several subsequent reaction steps.…”

“…[2] Herein we report on an intramolecularly donor-stabilized silaethene, 1-(8-dimethylamino-1-naphthyl)-1,2,2-tris(trimethylsilyl)silene (7), whose remarkable thermal stability and considerably limited reactivity are attributed to the intramolecular interaction of the 8-dimethylamino group of the naphthyl substituents with the silene-silicon atom. A stable dibenzosilafulvene with an 8-dimethylaminomethyl-1-naphthyl group at the Si atom, which could possibly also be regarded as an intramolecularly donor-stabilized silene, was isolated by Chernyshev and coworkers; [3] however, there is no X-ray crystal structure analysis of this compound.…”

Synthesis and Structural Characterization of Novel Silenes Stabilized by Intramolecular Coordination of a Dialkylamino Group

“…[4] Intramolecularly donor-stabilized silenes were unknown till now, possibly because of the lack of suitable synthetic methods. A stable dibenzosilafulvene with an 8-dimethylaminomethyl-1-naphthyl group at the silicon atom, which could possibly be regarded as a silene with intramolecular amine coordination, was isolated by Chernyshev and co-workers; [5] however, there is no X-ray crystal structure analysis of the compound. From theoretical calculations, performed in the group of Guselnikov, a definite stabilization of the SiC bond of silenes by intramolecular N 3 Si coordination was concluded.…”