Singlet - Triplet energy gaps in highly stabilized nitrenium ions: Experimental and theoretical study of 1,3-dimethylbenzotriazolium ion

Organic Letters

Volumn 2, Issue 16, 2000, Pages 2451-2454

  McIlroy, Sean ^a   Cramer, Christopher J ^b   Falvey, Daniel E ^a  

^a Bldg 142   (United States)

^b University of Minnesota   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0000225424     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol006106g     Document Type: Article

References (30)

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24. DFT calculations were carried out with Gaussian 98 augmented with MN-GSM version g1. CAS calculations were carried out with MOLCAS. See ref 27 for details.
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30. Thermal contributions to the enthalpies and free energies of the two spin states can be derived from the frequency calculations using standard statistical mechanical approximations. At 298 K these favor the triplet by about 3 kcal/mol. However, since measured rates of triplet energy transfer are not obviously tied to the fully equilibrated free energy difference between the singlet and triplet states of the nitrenium ion (i.e., there may be vertical character to the energy transfer and/or exciplexes may be involved), it is not obvious that inclusion of thermal contributions is more physical