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We describe a chiral phosphoric acid (CPA) catalyzed asymmetric [3+3] cycloaddition of N‐viny oxindole nitrones with 2‐indolylmethanols to prepare various spirooxindole[1,2]oxazines in 43–93% yields and 88:12–97:3 enantiomeric ratios. Experimental results revealed that the addition of hexafluoroisopropanol (HFIP) played important roles to help CPA control the reaction reactivity and enantioselectivity. The present method features the construction of a tetrasubstituted chiral carbon stereocenter and the example of N‐vinyl nitrones in asymmetric [3+3] cycloaddition. [ABSTRACT FROM AUTHOR]

The front cover illustrates a chiral phosphoric acid (CPA) catalyzed enantioselective [3+3] cycloaddition of N‐vinyl oxindole nitrones and 2‐indolylmethanols, which was utilized to prepare a variety of spirooxindole[1,2]oxazines. Details can be found in Communication by Wen‐Jun Zhou, and co‐workers (N. Zou, Y.‐Z. Wu, X.‐Y. Zhong, C. Wei, L.‐M. Liao, D.‐L. Mo, W.‐J Zhou, Adv. Synth. Catal. 2024, 366, 4962‐4967; DOI: 10.1002/adsc.202400533)).By Ning Zou; Yu‐Zheng Wu; Xin‐Yi Zhong; Cui Wei; Li‐Min Liao; Dong‐Liang Mo and Wen‐Jun ZhouReported by Author; Author; Author; Author; Author; Author; Author [Extracted from the article]