Copper‐ and Phosphane‐Free Sonogashira Coupling of Arenediazonium o‐Benzenedisulfonimides

Abstract

Arenediazonium o-benzenedisulfonimides can be used as efficient reagents in Sonogashira coupling reactions. In this work, reactions were carried out in DMSO under very mild conditions (without copper or phosphanes), and gave rise to arylated alkynes in good to excellent yields (25 examples, average yield 83 %). o-Benzenedisulfonimide could be reco- [a]598 vered from all the reactions in yields of Ͼ80 %, so it could be recycled for the preparation of other diazonium salts. Mechanistic insights revealed the fundamental roles of DMSO and the anion of o-benzenedisulfonimide in the formation of the catalyst, and also the importance of DMSO in the catalytic cycle.

Microwave‐Assisted Synthesis of Sulfurated Heterocycles with Herbicidal Activity: Reaction of 2‐Alkynylbenzoic Acids with Lawesson's Reagent

“…13 C NMR (126 MHz, CDCl 3 ): δ =160.5, 133.8, 133.2, 132.3, 128.4, 128.3, 127.4, 104.8, 86.9, 80.6, 51.4 ppm. Physical and spectroscopic data were in agreement with those reported in the literature …”

Dual gold/photoredox-catalyzed C(sp)–H arylation of terminal alkynes with diazonium salts

“…Arylation of the resulting alkynylgold complexes would deliver cross-coupled arylalkyne products in a dual gold and photoredox-catalyzed analogue of the widely-employed Sonogashira–Hagihara reaction. 8 , 9 As demonstrated below, this process benefits from mild conditions (room temperature, household light bulb) and broad functional group tolerance while making use of readily-available aryldiazonium salts as the arene coupling partner. Furthermore, by exploiting a non-conventional stepwise oxidation process of Au I complexes into active Au III species by means of organic radicals generated under photoredox catalysis, we have developed a very fast arylating system that proceeds under base-free conditions.…”

Recent Development of Aryl Diazonium Chemistry for the Derivatization of Aromatic Compounds

“…Transition metal-catalyzed Sonogashira-type cross-coupling reactions of aryl diazonium salts have opened an alternative avenue toward the synthesis of arylated alkynes (Scheme ). Under copper- and phosphane-free conditions, a Pd-catalyzed Sonogashira coupling reaction of aryl diazonium o -benzenedisulfonimides 107 with terminal alkynes 72 was developed . The o -benzenedisulfonimide can be recovered in greater than 80% yields.…”