Catalyst-Controlled Selectivity Switch in Three-Component Reaction: An NHC-Catalyzed Strategy for the Synthesis of δ-Lactone-Fused Spirobenzofuran-3-ones
Abstract
:1. Introduction
2. Results and Discussion
3. Materials and Methods
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Sample Availability
References
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Entry | Catalyst | Base | Solvent | Yield (%) b |
---|---|---|---|---|
1 | A | Cs2CO3 | toluene | 32 |
2 | B | Cs2CO3 | toluene | 55 |
3 | C | Cs2CO3 | toluene | 22 |
4 | D | Cs2CO3 | toluene | 11 |
5 | E | Cs2CO3 | toluene | 38 |
6 | F | Cs2CO3 | toluene | Trace d |
7 | G | Cs2CO3 | toluene | <5 |
8 | H | Cs2CO3 | toluene | Trace d |
9 | I | Cs2CO3 | toluene | Trace d |
10 | J | Cs2CO3 | toluene | <5 |
11 | B | DABCO | toluene | <5 |
12 | B | DBU | toluene | Trace d |
13 | B | DIPEA | toluene | <5 |
14 | B | DMAP | toluene | 20 |
15 | B | Et3N | toluene | 34 |
16 | B | NaOAc | toluene | <5 |
17 | B | K2CO3 | toluene | 22 |
18 | B | KOBu t | toluene | Trace d |
19 | B | Cs2CO3 | THF | 34 |
20 | B | Cs2CO3 | DCM | 12 |
21 | B | Cs2CO3 | CH3CN | Trace d |
22 | B | Cs2CO3 | anisole | 35 |
23 | B | Cs2CO3 | MTBE | 46 |
24 c | B | Cs2CO3 | toluene | 63 |
25 | - | Cs2CO3 | toluene | Trace d |
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Wang, Z.; Yang, T.; Liu, D.; Chen, R.; Wang, N.; Liu, H.; Li, J.; Wang, K.; Liu, H. Catalyst-Controlled Selectivity Switch in Three-Component Reaction: An NHC-Catalyzed Strategy for the Synthesis of δ-Lactone-Fused Spirobenzofuran-3-ones. Molecules 2022, 27, 5952. https://doi.org/10.3390/molecules27185952
Wang Z, Yang T, Liu D, Chen R, Wang N, Liu H, Li J, Wang K, Liu H. Catalyst-Controlled Selectivity Switch in Three-Component Reaction: An NHC-Catalyzed Strategy for the Synthesis of δ-Lactone-Fused Spirobenzofuran-3-ones. Molecules. 2022; 27(18):5952. https://doi.org/10.3390/molecules27185952
Chicago/Turabian StyleWang, Zhanyong, Ting Yang, Dongfang Liu, Rongxiang Chen, Nan Wang, Hong Liu, Jiarong Li, Kaikai Wang, and Hongxin Liu. 2022. "Catalyst-Controlled Selectivity Switch in Three-Component Reaction: An NHC-Catalyzed Strategy for the Synthesis of δ-Lactone-Fused Spirobenzofuran-3-ones" Molecules 27, no. 18: 5952. https://doi.org/10.3390/molecules27185952