Synthesis of Structurally Diversified Benzo[c]chromene Derivatives under (An)aerobic Conditions Catalyzed by CuI

Abstract

2‐Bromobenzoic acids underwent an α‐arylation with cyclohexane‐1,3‐diones to give 1H‐benzo[c]chromene‐1,6(2H)‐diones under Ar atmosphere catalyzed by CuI/l‐proline in the presence of Cs2CO3. The subsequent regioselective oxidation took place under O2 balloon automatically based on the substituents for the construction of structurally diversified benzo[c]coumarin derivatives.

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

“…6 As shown in Fig. 1, defucogilvocarcin V, 2 b isolated from the fermentation broth of Streptomyces arenae 2064, demonstrates antitumor activity, altenuisol, 2 a ,7 extracted from molds, possesses outstanding antibacterial activity, and thunberginol A, 4 a ,8 isolated from Hydrangeae Dulcis Folium , shows excellent anti-allergic activity. Thus, the development of a direct and effective protocol to synthesize isocoumarin frameworks remains highly desirable.…”

Synthesis of Esterified/Fused Isocoumarins via Rh-Catalyzed C—H Activation/Transannulative Coupling/Annulation of Phthalic Anhydrides with Cyclic 2-Diazo-1,3-diketones and Methanol

“…[4] A copper-catalyzed α-arylation of 1,3-cyclohexanedione with 2-bromobenzoic acids followed by intramolecular esterification for the synthesis of fused isocoumarins was firstly reported by McKillop group. [5] Subsequently, this methodology was further studied by the groups of Bryson, [6] Wang, [7] and Fan. [8] Recently, an impressive transition metal-free α-arylation/ring annulation and Rh-catalyzed direct C-H activation of ylides with diazo compounds have been developed for efficient access to fused isocoumarins.…”

Enantioselective Synthesis of Fused Isocoumarins via Palladium-Catalyzed Annulation of Alkyne-Tethered Malononitriles

“…In 1977, the Mckillop group reported a copper-catalyzed α-arylation of 1,3-cyclohexanedione with 2-bromobenzoic acids followed by intramolecular esterification for the synthesis of fused isocoumarins . This strategy was further investigated by the groups of Bryson, Wang, and Fan . Recently, an impressive transition-metal-free α-arylation/ring annulation process promoted by cesium carbonate was reported by Liang and co-workers .…”