Organic and Biomolecular Chemistry p. 2751 - 2759 (2011)
Update date:2022-08-05
Topics:
Yoo, Ellie Jung-Hwa
Feketeova, Linda
Khairallah, George N.
White, Jonathan M.
O'Hair, Richard A. J.
The fixed charge zwitterionic sulfur betaines dimethylsulfonioacetate (DMSA) (CH3)2S+CH2CO 2- and dimethylsulfoniopropionate (DMSP) (CH 3)2S+(CH2)2CO 2- have been synthesized and the structures of their protonated salts (CH3)2S+CH2CO 2H...Cl- [DMSA.HCl] and (CH3) 2S+(CH2)2CO2H... Pcr- [DMSP.HPcr] (where Pcr = picrate) have been characterized using X-ray crystallography. The unimolecular chemistry of the [M+H]+ of these betaines was studied using two techniques; collision-induced dissociation (CID) and electron-induced dissociation (EID) in a hybrid linear ion trap Fourier transform ion cyclotron resonance mass spectrometer. Results from the CID study show a richer series of fragmentation reactions for the shorter chain betaine and contrasting main fragmentation pathways. Thus while (CH 3)2S+(CH2)2CO 2H fragments via a neighbouring group reaction to generate (CH 3)2S+H and the neutral lactone as the most abundant fragmentation channel, (CH3)2S+CH 2CO2H fragments via a 1,2 elimination reaction to generate CH3S+CH2 as the most abundant fragment ion. To gain insights into these fragmentation reactions, DFT calculations were carried out at the B3LYP/6-311++G(2d,p) level of theory. For (CH3) 2S+CH2CO2H, the lowest energy pathway yields CH3S+CH2via a six-membered transition state. The two fragment ions observed in CID of (CH3) 2S+(CH2)2CO2H are shown to share the same transition state and ion-molecule complex forming either (CH3)2S+H or (CH2) 2CO2H+. Finally, EID shows a rich and relatively similar fragmentation channels for both protonated betaines, with radical cleavages being observed, including loss of CH3.
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Doi:10.1002/anie.201913057
(2020)Doi:10.1016/S0040-4020(01)81524-6
(1990)Doi:10.3390/molecules23112961
(2018)Doi:10.1021/ol200828s
(2011)Doi:10.1016/0022-328X(90)87209-V
(1990)Doi:10.1246/cl.1990.1395
(1990)