Revisiting Cyclobutadienemetal Complexes: High-Content Dewar Benzene Polymers and a One-Pot Synthesis of Permethylated Ladderanes

Michael J. Marsella; Samia Estassi; Li-Sheng Wang; Kunsang Yoon

doi:10.1055/s-2003-43348

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Revisiting Cyclobutadienemetal Complexes: High-Content Dewar Benzene Polymers and a One-Pot Synthesis of Permethylated Ladderanes

Michael J. Marsella*, Samia Estassi, Li-Sheng Wang, Kunsang Yoon
Department of Chemistry, University of California at Riverside, Riverside, California, 92521-0403 USA
Fax: +1(909)7872435; e-Mail: Michael.marsella@ucr.edu;

Abstract

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Abstract

High-content Dewar benzene polymers and sterically congested [n]-ladderanes have been synthesized from [4π_s+2π_s] cyclobutadienemetal complex cycloaddition chemistry. In the former case, tetramethylcyclobutadiene-AlCl₃ is reacted with an acetylene-containing precursor polymer to yield > 95% Dewar benzene incorporation. In the latter case, [n]-ladderanes containing up to thirteen rings are prepared via a one-pot procedure from 2-butyne.

Key words

polymer synthesis - Dewar benzene - [n]-ladderanes - cycloadditions - cyclobutadiene

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References

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