o triarylmethanes through decarboxylation †

CSIR-Central Drug Research Institute, BS Lucknow 226031, India. E-mail: gautam. es.in; Fax: +91-522-2771941; Tel: +91xt. 4662 rch, New Delhi 110001, India tion (ESI) available. See DOI: functionalized in the quest for new therapeutic agents and unexplored biologically relevant chemical spaces. Several triarylmethane based dyes were also developed as sensitizers, exhibiting selective phototoxicity towards cancerous cell lines and thus forms the basic principle of photodynamic therapy. These triarylmethanes exhibit interesting properties like photo lability, photo ionization which were successfully exploited for the development of many organic based dyes, photochromatic devices and uorescent probes. Apart from this, these class of compounds oen found their explosive growth in the construction of supramolecular architectures. Conventionally, triarylmethanes are synthesized through typical Friedel–Cras alkylation of diarylcarbinols with aromatic ring as nucleophile or hydroarylation of arenes with aromatic aldehydes or imines in the presence of either suitable Bronsted or Lewis acid systems. Recently, Crudden et al. reported the synthesis of triarylmethanes through arylative desulfonation whereas Chakravarty et al. reported Friedel–Cras reaction on benzylic phosphates for the synthesis of triarylmethanes. These procedures oen suffer from lack of selectivity, involves multistep synthesis andmoreover is limited to only electron rich arene systems. Due to this, cross coupling based strategies emerged as promising avenue for the short and efficient synthesis of triarylmethanes.Oshima et al. reported palladium catalyzed direct C–H bond activation of aryl(azaaryl)methanes for synthesis of triarylmethanes. L. A. López et al. reported zinc catalyzed cascade reaction between enynones and azoles resulting in the diversely substituted triarylmethanes synthesis. A reductive cross coupling was developed by Zhang et al. using benzophenone tosylhydrazones using palladium catalyst. Jarvo et al. synthesized enantioenriched triarylmethanes by stereospecic cross coupling in presence of nickel catalyst. Similarly, palladium catalysed C– H/C–O coupling of oxazoles with diarylmethanol derivatives have also been reported for synthesis of triarylmethanes. Decarboxylative cross coupling reaction has been emerged as a powerful strategy for C–C bond formation in the recent past