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Abstract Herein we report the MoO2Dipic promoted sulfonation of alkenes using N−Ts‐hydroxylamine as the quantitative source of Ts. The reaction works with high yields and stereoselectivities for styrenes with a wide variety of substitution patterns. A novel atom transfer radical addition mechanism involving the formation of molybdooxaziridine complex1as the active catalyst, difunctionalization withTs‐NO, followed by oxidation, and then elimination as the rate‐determining‐step for the formation of vinylsulfone3has been proposed. Initial kinetic and mechanistic data indicates the formation ofTs‐NOand provides evidence for the proposed mechanism.
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Direct Aniline Formation with Benzene and Hydroxylamine
A single-step method for aniline formation was examined. Using a vanadate catalyst with an iron oxide co-catalyst and hydroxylamine hydrochloride as the amine source, an up to 90% yield of aniline was obtained with high selectivity. Further study showed that the overall reaction was pseudo-second order in terms of hydroxylamine concentration. Regioselective H-D exchange experiments suggest that the C-N bond formation step occurs via an irreversible electrophilic pathway. Based on all of the key observations, a mechanism is proposed.
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- Award ID(s):
- 1725028
- PAR ID:
- 10464838
- Date Published:
- Journal Name:
- Chemistry
- Volume:
- 5
- Issue:
- 4
- ISSN:
- 2624-8549
- Page Range / eLocation ID:
- 2056 to 2067
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/chemistry5040139
