Rh(iii)-Catalyzed C(sp²)–H functionalization/cyclization cascade of N-carboxamide indole and iodonium reagents for access to indoloquinazolinone derivatives

Abstract

Rhodium-catalyzed synthesis of indoloquinazoline from readily available hypervalent iodonium reagent and N-carboxamide indole was developed. The protocol features broad functional group tolerance, mild conditions, excellent yields and simple workup. Notably,...

Divergent C(sp2)–H arylation of heterocycles via organic photoredox catalysis

“…Subsequently, we explored the reaction compatibility with different iodonium ylides using 1-methylquinoxalin-2(1H)-one 1a as the coupling partner (Scheme 3). The reaction exhibited an excellent tolerance of electron-donating (Me, Et, and tBu) and electron-withdrawing (CF 3 ) groups on the aryl ring of iodonium ylides at the para-position, affording the products in 67-87% yields (38)(39)(40)(41). The halogens (F, Cl and Br) also worked well and the corresponding products were obtained in 72-81% yields (42)(43)(44).…”

“…Hypervalent iodine(III) ylides (HVIs), as a stable singlet carbene precursor, have been used as important building blocks in organic synthesis due to their thermal stability, affordability and ease of availability. [33][34][35][36][37][38] The iodine atom of HVIs is less electronegative and strongly polarizable, which would lead to the property of double bonds between carbon and iodine atoms, and allow this carbon atom to easily coordinate with the metal center, subsequently applying to C-H functionalization, [39][40][41] C-C coupling reaction 42,43 and cyclization reaction. 44,45 Although the photo-induced decabonylation pathway with phenyl iodine(III) has been reported, 46 the photoredox reaction of HVIs is still in infancy.…”

Rh(iii)-catalyzed C–H annulation of sulfoxonium ylides with iodonium ylides towards isocoumarins

“…Moreover, iodonium ylides, with low toxicity and excellent solubility, have been widely used in carbine catalysis. 19 Taking into account the potential application of sulfoxonium ylides in the synthesis of cyclic compounds, the development of isocoumarins and our interest in transition-metal catalyzed C–H activation reactions, 20 herein, we describe a facile Rh( iii )-catalyzed annulated coupling of sulfoxonium ylides and iodonium ylides to synthesize multi-substituted isocoumarins, avoiding the presence of oxidants under mild reaction conditions (Scheme 1c).…”

Transition Metal-Free, Methoxide-Catalyzed Synthesis of Pyridoindolones

“…Dihydropyrido­[1,2- a ]­indolone derivatives (DHPIs) are N -fused polycyclic indoles contained in the core structure of indole alkaloids and medicines (Figure ). These compounds exhibit a wide range of bioactivities, for example, the FK-1052 is an orally active serotonin receptor antagonist demonstrating antiemetic effects generated by cancer chemotherapy . The Hsp 90 inhibitor is becoming increasingly relevant as anticancer medicines .…”