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

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

References

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Calculations were performed using Titan computational software, Schrodinger, Inc., 1500 SW First Avenue, Suite 1180, Portland, Oregon 97201.