On-surface cyclodehydrogenation reaction pathway determined by selective molecular deuterations

Chuanxu Ma; Zhongcan Xiao; Peter V. Bonnesen; Liangbo Liang; Alexander A. Puretzky; Jingsong Huang; Marek Kolmer; Bobby G. Sumpter; Wenchang Lu; Kunlun Hong; Jerzy Bernholc; An Ping Li

doi:10.1039/d1sc04908a

On-surface cyclodehydrogenation reaction pathway determined by selective molecular deuterations

Chuanxu Ma, Zhongcan Xiao, Peter V. Bonnesen, Liangbo Liang, Alexander A. Puretzky, Jingsong Huang, Marek Kolmer, Bobby G. Sumpter, Wenchang Lu, Kunlun Hong, Jerzy Bernholc, An Ping Li

Research output: Contribution to journal › Article › peer-review

13 Scopus citations

Abstract

Understanding the reaction mechanisms of dehydrogenative Caryl-Caryl coupling is the key to directed formation of π-extended polycyclic aromatic hydrocarbons. Here we utilize isotopic labeling to identify the exact pathway of cyclodehydrogenation reaction in the on-surface synthesis of model atomically precise graphene nanoribbons (GNRs). Using selectively deuterated molecular precursors, we grow seven-atom-wide armchair GNRs on a Au(111) surface that display a specific hydrogen/deuterium (H/D) pattern with characteristic Raman modes. A distinct hydrogen shift across the fjord of Caryl-Caryl coupling is revealed by monitoring the ratios of gas-phase by-products of H2, HD, and D2 with in situ mass spectrometry. The identified reaction pathway consists of a conrotatory electrocyclization and a distinct [1,9]-sigmatropic D shift followed by H/D eliminations, which is further substantiated by nudged elastic band simulations. Our results not only clarify the cyclodehydrogenation process in GNR synthesis but also present a rational strategy for designing on-surface reactions towards nanographene structures with precise hydrogen/deuterium isotope labeling patterns.

Original language	English
Pages (from-to)	15637-15644
Number of pages	8
Journal	Chemical Science
Volume	12
Issue number	47
DOIs	https://doi.org/10.1039/d1sc04908a
State	Published - Dec 21 2021

Funding

This research was conducted at the Center for Nanophase Materials Sciences (CNMS), which is a U.S. DOE Office of Science User Facility. C. M. acknowledges supports from the National Natural Science Foundation of China (Grant No. 12074359 and 22002149) and the Chinese Academy of Sciences (CAS). The electronic characterization was funded by ONR grants N00014-20-1-2302 and N00014-16-1-3153. The supercomputer time was provided by NSF grant OCI-1036215 at the National Center for Supercomputing Applications (NSF OCI-0725070 and ACI-1238993) and the Oak Ridge Leadership Computing Facility, which is a U.S. DOE Office of Science User Facility supported under Contract No. DE-AC05-00OR22725. M. K. acknowledges support from LDRD program at Ames Laboratory, which is operated for the U.S. DOE by Iowa State University under Contract No. DE-AC02-07CH11358.

Access to Document

10.1039/d1sc04908a

Cite this

@article{06e3e95f99794052b66aa2f4ee9bcf85,

title = "On-surface cyclodehydrogenation reaction pathway determined by selective molecular deuterations",

abstract = "Understanding the reaction mechanisms of dehydrogenative Caryl-Caryl coupling is the key to directed formation of π-extended polycyclic aromatic hydrocarbons. Here we utilize isotopic labeling to identify the exact pathway of cyclodehydrogenation reaction in the on-surface synthesis of model atomically precise graphene nanoribbons (GNRs). Using selectively deuterated molecular precursors, we grow seven-atom-wide armchair GNRs on a Au(111) surface that display a specific hydrogen/deuterium (H/D) pattern with characteristic Raman modes. A distinct hydrogen shift across the fjord of Caryl-Caryl coupling is revealed by monitoring the ratios of gas-phase by-products of H2, HD, and D2 with in situ mass spectrometry. The identified reaction pathway consists of a conrotatory electrocyclization and a distinct [1,9]-sigmatropic D shift followed by H/D eliminations, which is further substantiated by nudged elastic band simulations. Our results not only clarify the cyclodehydrogenation process in GNR synthesis but also present a rational strategy for designing on-surface reactions towards nanographene structures with precise hydrogen/deuterium isotope labeling patterns.",

author = "Chuanxu Ma and Zhongcan Xiao and Bonnesen, {Peter V.} and Liangbo Liang and Puretzky, {Alexander A.} and Jingsong Huang and Marek Kolmer and Sumpter, {Bobby G.} and Wenchang Lu and Kunlun Hong and Jerzy Bernholc and Li, {An Ping}",

note = "Publisher Copyright: {\textcopyright} The Royal Society of Chemistry.",

year = "2021",

month = dec,

day = "21",

doi = "10.1039/d1sc04908a",

language = "English",

volume = "12",

pages = "15637--15644",

journal = "Chemical Science",

issn = "2041-6520",

publisher = "Royal Society of Chemistry",

number = "47",

}

TY - JOUR

T1 - On-surface cyclodehydrogenation reaction pathway determined by selective molecular deuterations

AU - Ma, Chuanxu

AU - Xiao, Zhongcan

AU - Bonnesen, Peter V.

AU - Liang, Liangbo

AU - Puretzky, Alexander A.

AU - Huang, Jingsong

AU - Kolmer, Marek

AU - Sumpter, Bobby G.

AU - Lu, Wenchang

AU - Hong, Kunlun

AU - Bernholc, Jerzy

AU - Li, An Ping

PY - 2021/12/21

Y1 - 2021/12/21

N2 - Understanding the reaction mechanisms of dehydrogenative Caryl-Caryl coupling is the key to directed formation of π-extended polycyclic aromatic hydrocarbons. Here we utilize isotopic labeling to identify the exact pathway of cyclodehydrogenation reaction in the on-surface synthesis of model atomically precise graphene nanoribbons (GNRs). Using selectively deuterated molecular precursors, we grow seven-atom-wide armchair GNRs on a Au(111) surface that display a specific hydrogen/deuterium (H/D) pattern with characteristic Raman modes. A distinct hydrogen shift across the fjord of Caryl-Caryl coupling is revealed by monitoring the ratios of gas-phase by-products of H2, HD, and D2 with in situ mass spectrometry. The identified reaction pathway consists of a conrotatory electrocyclization and a distinct [1,9]-sigmatropic D shift followed by H/D eliminations, which is further substantiated by nudged elastic band simulations. Our results not only clarify the cyclodehydrogenation process in GNR synthesis but also present a rational strategy for designing on-surface reactions towards nanographene structures with precise hydrogen/deuterium isotope labeling patterns.

AB - Understanding the reaction mechanisms of dehydrogenative Caryl-Caryl coupling is the key to directed formation of π-extended polycyclic aromatic hydrocarbons. Here we utilize isotopic labeling to identify the exact pathway of cyclodehydrogenation reaction in the on-surface synthesis of model atomically precise graphene nanoribbons (GNRs). Using selectively deuterated molecular precursors, we grow seven-atom-wide armchair GNRs on a Au(111) surface that display a specific hydrogen/deuterium (H/D) pattern with characteristic Raman modes. A distinct hydrogen shift across the fjord of Caryl-Caryl coupling is revealed by monitoring the ratios of gas-phase by-products of H2, HD, and D2 with in situ mass spectrometry. The identified reaction pathway consists of a conrotatory electrocyclization and a distinct [1,9]-sigmatropic D shift followed by H/D eliminations, which is further substantiated by nudged elastic band simulations. Our results not only clarify the cyclodehydrogenation process in GNR synthesis but also present a rational strategy for designing on-surface reactions towards nanographene structures with precise hydrogen/deuterium isotope labeling patterns.

UR - http://www.scopus.com/inward/record.url?scp=85121118805&partnerID=8YFLogxK

U2 - 10.1039/d1sc04908a

DO - 10.1039/d1sc04908a

M3 - Article

AN - SCOPUS:85121118805

SN - 2041-6520

VL - 12

SP - 15637

EP - 15644

JO - Chemical Science

JF - Chemical Science

IS - 47

ER -

On-surface cyclodehydrogenation reaction pathway determined by selective molecular deuterations

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this