Synthesis and Structural Characterization of Butadienylcalcium-based Heavy Grignard Reagents and a Ca4 [O] Inverse Crown Ether Complex

Baosheng Wei; Liang Liu; Wen-Xiong Zhang; Zhenfeng Xi

doi:10.1002/anie.201704176

Synthesis and Structural Characterization of Butadienylcalcium-based Heavy Grignard Reagents and a Ca₄ [O] Inverse Crown Ether Complex

Angew Chem Int Ed Engl. 2017 Jul 24;56(31):9188-9192. doi: 10.1002/anie.201704176. Epub 2017 Jun 29.

Authors

Baosheng Wei¹, Liang Liu¹, Wen-Xiong Zhang¹, Zhenfeng Xi^{1

2}

Affiliations

¹ Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, China.
² State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Shanghai, 200032, China.

PMID: 28593729
DOI: 10.1002/anie.201704176

Abstract

The structure elucidation of heavy Grignard reagents (RAeX, Ae=Ca, Sr, and Ba, X=halides) has been greatly strived after, mainly because of their inaccessibility and remarkable instability. The synthesis of a series of butadienylcalcium compounds is presented, including 1-calcio-4-lithio-1,3-butadiene, 1,4-dicalcio-1,3-butadiene, and a Ca₄ [O] inverse crown ether complex, via the reaction between 1,4-dilithio-1,3-butadienes and calcium iodide in THF. Single-crystal X-ray analysis of these unprecedented heavy Grignard reagents revealed unique structural characteristics and bonding modes. Preliminary reaction chemistry was investigated. This study provides a novel class of alkenyl heavy Grignard reagents and a useful synthetic strategy for otherwise unavailable reactive organometallic compounds.

Keywords: butadienylcalcium compounds; heavy Grignard reagents; inverse crown ether; organocalcium compounds.

Publication types

Research Support, Non-U.S. Gov't