Structure reactivity relationship in the accelerated formation of 2,3-diarylquinoxalines in the microdroplets of a nebuliser
Publication date
2019-12-01Author
Hayat, NadiaFenwick, Nathan W.
Saidykhan, Amie
Telford, Richard
Martin, William H.C.
Gallagher, R.T.
Bowen, Richard D.
Peer-Reviewed
Yes
Metadata
Show full item recordAbstract
Competition experiments in which 1,2-phenylenediamine, C6H4(NH2)2, condenses with equimolar quantities of benzil, (C6H5CO)2, and a 3,3'- or 4,4'-disubstituted benzil (XC6H4CO)2 (X = F, Cl, Br, CH3 or CH3O) to form a mixture of 2,3-diphenylquinoxaline and the corresponding 2,3-diarylquinoxaline (Ar = XC6H4) in the microdroplets produced in a nebuliser allow a Hammett relationship with a ρ value of 1.85 to be developed for this accelerated condensation in the nebuliser. This structure reactivity relationship reveals that an appreciable amount of negative charge builds up on the carbon of the carbonyl group of the benzil during the rate-limiting step of the reaction, thus confirming that this process involves nucleophilic addition of the 1,2-phenylenediamine to the benzil. In general, the presence of an electron donating substituent, particularly in the 4 and 4' positions, in the benzil retards the reaction, whereas an electron attracting substituent, especially in the 3 and 3' position, accelerates it.Version
No full-text in the repositoryCitation
Hayat N, Fenwick NW, Saidykhan A, Telford R et al (2019) Structure reactivity relationship in the accelerated formation of 2,3-diarylquinoxalines in the microdroplets of a nebuliser. European Journal of Mass Spectrometry. 25(6): 457-462.Link to Version of Record
https://doi.org/10.1177/1469066719877346Type
Letterae974a485f413a2113503eed53cd6c53
https://doi.org/10.1177/1469066719877346