Analogs of Michler’s ketone for two-photon absorption initiation of polymerization in the near infrared: synthesis and photophysical properties

Abstract

We present the synthesis of substituted ketones, conjugated analogs of Michler’s ketone. These molecules exhibit broadband TPA properties between 700 and 1100 nm due to a charge transfer from the terminal amino groups to the central ketone function and with maximum cross sections from 200 to 325 × 10⁻⁵⁰ cm⁴ s photon⁻¹. Moreover, they present an interesting reducing character for radical creation. Both properties allow us to consider these molecules as promising photoinitiators of polymerization in the near infrared.