**Xue Yan 1,2, Ying-De Tang 1,2, Cheng-Shi Jiang 2, Xigong Liu 2,3,\* and Hua Zhang 2,\***


Received: 23 December 2019; Accepted: 15 January 2020; Published: 20 January 2020

**Abstract:** The oxidative, dearomative cross-dehydrogenative coupling of indoles with various C-H nucleophiles is developed. This process features a broad substrate scope with respect to both indoles and nucleophiles, affording structurally diverse 2,2-disubstituted indolin-3-ones in high yields (up to 99%). The oxidative dimerization and trimerization of indoles has also been demonstrated under the same conditions.

**Keywords:** cross coupling; dearomatization; C-H functionalization; indolin-3-ones; dimerization and trimerization of indoles
