Highly Selective On-Surface [2 + 2] Cycloaddition Induced by Hierarchical Metal-Organic Hybrids
Jiahao Xi1, Renjie Xue1, Xuechao Li1
1Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou 215123, Jiangsu, P. R. China.
The Journal of Physical Chemistry Letters
|February 7, 2023
Summary
Surface synthesis of phenylenes achieves selectivity via metal-organic hybrids (MOHs). Debromination of 2,3-dibromophenazine (DBPZ) on Ag(111) yields uniform products, unlike on Au(111).
Area of Science:
- Surface science
- Organic chemistry
- Materials science
Background:
- On-surface synthesis of phenylenes enables π-conjugated frameworks.
- Achieving uniform products remains a challenge due to selectivity issues.
Purpose of the Study:
- Investigate the debromination of 2,3-dibromophenazine (DBPZ) on Au(111) and Ag(111) surfaces.
- Understand the role of metal-organic hybrids (MOHs) in reaction selectivity.
Main Methods:
- On-surface synthesis
- Scanning tunneling microscopy (STM)
- Bond-resolved atomic force microscopy (BR-AFM)
Main Results:
- On Au(111), debromination leads to immediate [2 + 2] and [2 + 2 + 2] cycloadditions.
- On Ag(111), sequential annealing forms MOHs, resulting exclusively in uniform [2 + 2] cycloaddition products.
- Chemical structures of intermediates and MOHs were elucidated.
Conclusions:
- Hierarchical evolution of MOHs on Ag(111) steers chemical selectivity.
- This study reveals a new pathway for controlled on-surface synthesis of uniform phenylenes.
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