Correction: Diastereoselective synthesis of tetrahydrobenzo[b]azocines by Lu(OTf)₃-catalyzed [4+4] cycloaddition of donor–acceptor cyclobutanes with anthranils

Abstract

Correction for ‘Diastereoselective synthesis of tetrahydrobenzo[b]azocines by Lu(OTf)3-catalyzed [4+4] cycloaddition of donor–acceptor cyclobutanes with anthranils’ by Meifeng Hou et al., Chem. Commun., 2022, 58, 5865–5868, https://doi.org/10.1039/D2CC00829G.

Lewis acid-catalyzed [4 + 2] cycloaddition of donor–acceptor cyclobutanes with iminooxindoles: access to spiro[piperidine-3,2′-oxindoles]

“…Catalysts such as Y(OTf) 3 , Hf(OTf) 4 , In(OTf) 3 , Cu(OTf) 2 , Lu(OTf) 3 and Nd(OTf) 3 result in low efficiency (Table 1, entries 4-9). To improve the yield, Lewis acids, including iron salts, tin salts and other kinds of Lewis acids, were also tested, and the results are unsatisfactory (Table 1, entries [10][11][12][13][14][15][16][17][18][19]. The yield decreased when the reaction was carried out in DCE, toluene and CHCl 3 (Table 1, entries 20-22).…”

“…Recently, we reported a Lu(OTf) 3 -catalyzed [4 + 4] cycloaddition reaction of D–A cyclobutanes with anthranils to deliver oxa-bridged eight-membered heterocycles. 10 Owing to our continuous interest in Lewis acid catalyzed reactions, 11 particularly in D–A cyclobutanes involved transformations, we envisioned that, upon suitable activation by acid, the reaction of D–A cyclobutanes and iminooxindoles would provide a new approach to deliver diverse spiro[piperidine-3,2′-oxindoles] ( Scheme 1b ).…”