PdCl₂/CuCl₂/Bi(OTf)₃‐promoted Construction of Sulfonyl Dibenzooxabicyclo[3.3.1]nonanes and Arylnaphthalenes via Intramolecular Annulation of Sulfonyl o‐Allylarylchromanones

Abstract

PdCl 2 /CuCl 2 /Bi(OTf) 3-promoted intramolecular domino annulation of sulfonyl o-allylarylchromanones provides tetracyclic sulfonyl dibenzooxabicyclo[3.3.1]nonanes and bicyclic arylnaphthalenes with good to excellent yields in MeOH at room (25°C) and refluxing (65°C) temperature, respectively. The starting sulfonyl o-allylarylchromanones can be easily obtained from the intermolecular cyclocondensation of αsulfonyl o-hydroxyacetophenones and o-allylbenzaldehydes. The uses of various catalysts and solvent systems are investigated herein for convenient transformation. A plausible mechanism is proposed and discussed. This protocol provides one-pot ring closure via carbon-carbon (CÀ C) bond formation.

Bi(OTf)3‐Mediated (4+1) Annulation of α‐Sulfonyl o‐Hydroxyacetophenones with α‐Hydroxy Arylketones to Access Sulfonyl 2‐Aroylbenzofurans

“…1). On the other hand, the reaction of 2 x [46] with 3 a did not produce 7 b under the standard conditions (Scheme 7, eq. 2).…”

Construction of Sulfonyl Dibenzofused Medium‐Size Oxacycles via Bi(OTf)3‐Catalyzed Friedel‐Crafts‐Type Annulation

“…To the best of our knowledge, flexible methods for synthesizing sulfonyl‐containing dibenzofused medium‐size rings have not been reported so far. Based on our recent experiences with regard to the one‐pot tandem Bi(OTf) 3 ‐catalyzed synthesis of sulfonyl‐containing benzofused skeletons (i. e., 1‐aryl isoquinolinones, [9a] 2‐aroyl benzofurans, [9b] dibenzooxabicyclo[3.3.1]nonanes), [9c] we developed a Bi(OTf) 3 ‐catalyzed approach to achieve a series of versatile 4 using two starting o ‐hydroxy acetophenones 2 and benzofused cycloethers 3 in MeNO 2 at 60 °C under the open‐vessel reaction condition. In the sequential cyclization procedure, 4 could be constructed via cascade single‐bond formation of carbon‐carbon and carbon‐oxygen single bonds.…”

One‐Pot Construction of Sulfonyl Benzonorcaradienes

“…Synthetic methods to install sulfonyl moieties into key core skeletons have been reported in the fields of organic and pharmaceutical chemistry owing to their chemoselectivity and bioactivity. [8,9] Inspired by recent synthetic reports on one-pot tandem condensation for the facile synthesis of diversified sulfonyl-conjugated frameworks, [10] herein we installed a sulfonyl substituent into the tricyclo[6.6.3] skeleton via one-pot stereocontrolled cyclization via the base-mediated tandem annulation of o-bis-sulfonylmethyl arenes with diversified α,β-unsaturated carbonyls.…”