Visible-Light Induced Copper-Catalyzed C—C Bond Cleavage/Coupling of Spiro Dihydroquinazolinones with Isatins: a Synthetic Method to 3-Alkyl-3-hydroxy-2-oxindoles

doi:10.6023/cjoc202601003

Chinese Journal of Organic Chemistry ›› 2026, Vol. 46 ›› Issue (4): 1685-1698.DOI: 10.6023/cjoc202601003 Previous Articles Next Articles

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可见光诱导铜催化螺二氢喹唑啉酮与靛红的碳碳键裂解/偶联: 一种合成3-烷基-3-羟基-2-氧化吲哚的方法

陈鑫^a^,^†, 王树涛^a^,^†, 杨文鹏^a, 王楚阳^a, 段新华^a^,^b^,^*(), 郭丽娜^a^,^*()

^a 西安交通大学化学学院西安 710049
^b 兰州大学天然产物化学国家重点实验室兰州 730000

收稿日期:2026-01-03 修回日期:2026-02-06 发布日期:2026-03-20
通讯作者: 段新华, 郭丽娜
作者简介:
^†共同第一作者.
基金资助:
国家自然科学基金(22571245)

Visible-Light Induced Copper-Catalyzed C—C Bond Cleavage/Coupling of Spiro Dihydroquinazolinones with Isatins: a Synthetic Method to 3-Alkyl-3-hydroxy-2-oxindoles

Xin Chen^a, Shutao Wang^a, Wen-Peng Yang^a, Chuyang Wang^a, Xin-Hua Duan^a^,^b^,^*(), Li-Na Guo^a^,^*()

^a School of Chemistry, Xi'an Jiaotong University, Xi'an 710049
^b State Key Laboratory of Natural Product Chemistry, Lanzhou University, Lanzhou 730000

Received:2026-01-03 Revised:2026-02-06 Published:2026-03-20
Contact: Xin-Hua Duan, Li-Na Guo
About author:
^†These authors contributed equally to this work.
Supported by:
National Natural Science Foundation of China(22571245)

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Abstract

A visible-light induced copper-catalyzed C—C cleavage/coupling reaction of spiro dihydroquinazolinones with isatins was reported. Using 30 W blue LED as the light source and Cu(NO₃)₂ as the catalyst, a series of 3-alkyl-3-hydroxy- 2-oxindoles bearing a quinazolin-4(3H)-one motif were efficiently synthesized at room temperature. This method features mild reaction conditions, operational simplicity, free of external photosensitizers and high atom economy. Detailed mechanistic studies suggest the formation of an electron donor-acceptor (EDA) complex in the reaction.

Key words: visible-light induced, copper-catalyzed, isatin, 3-alkyl-3-hydroxy-2-oxindole, electron donor-acceptor (EDA) complex

Cite this article

Xin Chen, Shutao Wang, Wen-Peng Yang, Chuyang Wang, Xin-Hua Duan, Li-Na Guo. Visible-Light Induced Copper-Catalyzed C—C Bond Cleavage/Coupling of Spiro Dihydroquinazolinones with Isatins: a Synthetic Method to 3-Alkyl-3-hydroxy-2-oxindoles[J]. Chinese Journal of Organic Chemistry, 2026, 46(4): 1685-1698.

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Fig. & Tab. 9

Figure 1. Natural products or bioactive molecules containing 3-alkyl-3-hydroxy-2-oxindoles

Scheme 1. Synthesis of 3-alkyl-3-hydroxy-2-oxindoles from isatin

Entry	Variation from standard conditions	Yield^b/% of 3a
1	None	77
2	DMAc, DMF, NMP as solvent	62, <10, <10
3	Cu(OTf)₂, CuOTf as catalyst	59, 58
4	Co(OAc)₂ as catalyst	43
5	Fe(OTf)₃, Ga(OTf)₃ as catalyst	<10
6	365, 390 nm Purple LEDs	Trace, 43
7	510 nm Green LEDs	Trace
8	Under air	13
9	In the dark	n.r.
10	No Cu(NO₃)₂	0 (57)^c

Table 1. Optimization of the reaction conditionsa

Table 2. Substrate scope of isatinsa

Table 3. Substrate scope of spiro dihydroquinazolinonesa

Scheme 2. Application investigations

Figure 2. Mechanism studies

Figure 3. Computational study

Scheme 3. Proposed mechanism

References 22

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可见光诱导铜催化螺二氢喹唑啉酮与靛红的碳碳键裂解/偶联: 一种合成3-烷基-3-羟基-2-氧化吲哚的方法

Visible-Light Induced Copper-Catalyzed C—C Bond Cleavage/Coupling of Spiro Dihydroquinazolinones with Isatins: a Synthetic Method to 3-Alkyl-3-hydroxy-2-oxindoles

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