Carbamate-Functionalized NLOphores via a Formal [2+2] Cycloaddition-Retroelectrocyclization Strategy.

This study introduces a new donor group capable of activating click-type [2+2] cycloaddition-retroelectrocyclizations, generally known for their limited scope. Target chromophores were synthesized using isocyanate-free urethane synthesis. The developed synthetic method allows for the tuning of the optical properties of the chromophores by modifying the donor groups, the acceptor units, and the side chains.