Highly oxidized products from the atmospheric reaction of hydroxyl radicals with toluene
Abstract
Simple aromatics, largely toluene (C ₇ H ₈ ) and benzene (C ₆ H ₆ ), are emitted into Earth´s atmosphere by different sources. Their degradation initiated by the gas-phase reaction with hydroxyl radicals (OH) forms mainly bicyclic peroxy radicals (BCP) besides phenol-type compounds. The formation of highly oxidized products with at least 6 O atoms (HOMs) starting from BCP is currently controversial. Here, the experimental observation of HOMs and other products is reported for near-atmospheric conditions focusing on OH + toluene. Autoxidation processes starting from BCP generate C ₇ H ₉ O ₇ and C ₇ H ₉ O ₉ radicals with molar yields of 0.25 −0.13 +0.25 % 0.25 − 0.13 + 0.25 % and 0.12 −0.06 +0.12 % 0.12 − 0.06 + 0.12 % , respectively. Labeling experiments revealed that the ring H atoms are involved in autoxidation. The atmospherically relevant reaction of C ₇ H ₉ O ₇ and C ₇ H ₉ O ₉ with NO almost exclusively forms organic nitrates as HOM products, C ₇ H ₉ O ₆₋₈ NO ₂ , with a total molar yield ≤ 0.1%. Other HOMs, such as C ₇ H ₈ O ₈ and C ₇ H ₈ O ₁₀ , represent only small trace products. Results from OH + benzene confirmed the findings from the toluene system pointing to a minor relevance of both aromatics for HOM generation.
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BibTeX
@article{berndt2026highly,
title = {{Highly oxidized products from the atmospheric reaction of hydroxyl radicals with toluene}},
author = {Torsten Berndt},
journal = {Communications Chemistry},
year = {2026},
month = oct,
doi = {10.1038/s42004-026-02230-0},
url = {https://www.nature.com/articles/s42004-026-02230-0},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Highly oxidized products from the atmospheric reaction of hydroxyl radicals with toluene
AU - Torsten Berndt
PY - 2026
DA - 2026/10/08
JO - Communications Chemistry
DO - 10.1038/s42004-026-02230-0
UR - https://www.nature.com/articles/s42004-026-02230-0
AB - Simple aromatics, largely toluene (C ₇ H ₈ ) and benzene (C ₆ H ₆ ), are emitted into Earth´s atmosphere by different sources. Their degradation initiated by the gas-phase reaction with hydroxyl radicals (OH) forms mainly bicyclic peroxy radicals (BCP) besides phenol-type compounds. The formation of highly oxidized products with at least 6 O atoms (HOMs) starting from BCP is currently controversial. Here, the experimental observation of HOMs and other products is reported for near-atmospheric conditions focusing on OH + toluene. Autoxidation processes starting from BCP generate C ₇ H ₉ O ₇ and C ₇ H ₉ O ₉ radicals with molar yields of 0.25_ −0.13^ +0.25 % 0.25 − 0.13 + 0.25 % and 0.12_ −0.06^ +0.12 % 0.12 − 0.06 + 0.12 % , respectively. Labeling experiments revealed that the ring H atoms are involved in autoxidation. The atmospherically relevant reaction of C ₇ H ₉ O ₇ and C ₇ H ₉ O ₉ with NO almost exclusively forms organic nitrates as HOM products, C ₇ H ₉ O ₆₋₈ NO ₂ , with a total molar yield ≤ 0.1%. Other HOMs, such as C ₇ H ₈ O ₈ and C ₇ H ₈ O ₁₀ , represent only small trace products. Results from OH + benzene confirmed the findings from the toluene system pointing to a minor relevance of both aromatics for HOM generation.
SN - 2399-3669
ER -