This work reports Xantphos‐coordinated palladium dithiolate complexes as catalysts for decarboxylative Sonogashira coupling reaction of phenyl propiolic acid and 2‐butynoic acid with various iodoarenes. These palladium aryl dithiolate complexes were synthesized and characterized by 1H and 31P nuclear magnetic resonance (NMR) spectroscopy, melting point, and elemental analysis (CHNS). Synthetic utility for the reported protocol is explored for the effect of various functional groups on the yield of corresponding heteroaryl alkynes. The current protocol showed excellent catalytic activity towards decarboxylative alkynylation reaction with high turn‐over number (TON) up to 105 and turn‐over frequency (TOF) up to 104 h−1. The catalyst could be recycled up to six recycles without losing its catalytic activity. The in situ generation of palladium nanoparticles (PdNPs) was observed after the third recycle, and the amount was significant after the sixth recycle, which were confirmed and characterized by powder X‐ray diffraction (XRD), scanning electron microscope (SEM), and energy‐dispersive X‐ray (EDX) analysis and high‐resolution transmission electron microscopy (HR‐TEM). The catalytic activity of the reaction is attributed to the formation of PdNPs.

An effective process for synthesizing 2-substituted indoles in a one-pot tandem reaction of 1-halo-2-nitrobenzene and terminal alkynes through addition/reductive cyclization is presented. This protocol involves a Sonogashira-type coupling reaction followed by reductive cyclization employing dppf (1,1'bis(diphenylphosphino)ferrocene) ligated Pd dithiolate complex as a catalyst and Zn as an inexpensive reductant. This efficient and tandem process tolerates broad functional groups with moderate to good yields. The gram-scale synthesis of 2substituted indole has also been demonstrated. This protocol provides an alternative route for the synthesis of 2-substituted indoles.

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A simple, cost-effective, and straightforward method for the synthesis of 2,3-disubstituted indole scaffolds has been developed. The present protocol involves copper-mediated tandem hydroamination followed by C–H annulation of unprotected anilines with a wide range of internal alkynes. In the presence of Cu(OAc)2·H2O and trifluoroacetic acid (TFA), the reaction proceeds well to afford a variety of substituted indole derivatives in moderate to good yields. This process was found to be compatible with both primary and secondary anilines coupled with aromatic/aliphatic alkynes. High-purity copper nanoparticles can be recovered after the reaction, revealing the cost-effectiveness and environmentally benign feature of the current protocol.

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