3877-15-4Relevant articles and documents
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Haines et al.
, p. 549,554 (1956)
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Generation of VBr? VBi? VO?? defect clusters for 1O2 production for molecular oxygen activation in photocatalysis
Ding, Jie,Dai, Zan,Tian, Fan,Zhou, Bo,Zhao, Bin,Zhao, Huiping,Chen, Zhiquan,Liu, Yunling,Chen, Rong
supporting information, p. 23453 - 23459 (2017/11/30)
Defect engineering on a semiconductor surface can provide coordinatively unsaturated sites for molecular oxygen activation in photocatalysis. In this work, we demonstrated that the vacancy type was key to modulate the molecular oxygen activation process on BiOBr nanosheets. By regulating the reaction time, an oxygen vacancy (VO??), a double atom defect cluster (VBi? VO??) and triple atom clusters (VBi? VO?? VBi? and VBr? VBi? VO??) were accordingly generated on the surface, subsurface and bulk of BiOBr. More importantly, the newly-discovered VBr? VBi? VO?? defect cluster was highly related to the singlet oxygen (1O2) production ability of BiOBr. Meanwhile, the excellent photocatalytic selective oxidation reactions were successfully realized over BiOBr with the VBr? VBi? VO?? defect cluster. In addition, time-dependent defect cluster generation and the associated molecular oxygen activation were discussed.
GENERATION OF CHALCOGENIDE ANIONS IN HYDRAZINE HYDRATE MEDIUM
Turchaninova, L. P.,Korchevin, N. A.,Deryagina, E. N.,Trofimov, B. A.,Voronkov, M. G.
, p. 125 - 126 (2007/10/02)
Aromatic thiols and dichalcogenides in hydrazine hydrate are effective generators of chalcogenide ions that will react with organyl halides to form diorganyl chalcogenides.Alkanethiols and dialkyl dichalcogenides are less effective in reaction with organyl chalcogenides.
Elimination reactions: Experimental confirmation of the predicted elimination of (β-cyanoethyl)sulfonium ions through a concerted, E2 mechanism
Banait, Narinder S.,Jencks, William P.
, p. 6950 - 6958 (2007/10/02)
Extrapolation of the lifetimes of carbanion intermediates formed in the elimination reactions of a series of β-cyanoethyl thioethers with different leaving groups (J. Am. Chem. Soc. 1988, 110, 5087-5095) predicts that the carbanions will not have a significant lifetime for pKlg a 2SO/H2O, 25.0 °C). Values of βlg obtained from Br?nsted-type plots of log kB against the estimated pKa values of the leaving groups, decrease from 0.39 to 0.24 with increasing pKa of the base catalyst. The changes in β and βlg are described by the interaction coefficient pxy=d?βlg/?pK BH=?βlg/?KBH=0.026. The deuterium isotope effect for proton removal from Ph-S+(Me)-CH2CL2CN is kH/kD=4.4 and 4.9 for tris(hydroxymethyl)aminomethane and ethylamine buffers, respectively, and there is no detectable protium exchange into the deuterated substrate. The positive pxy coefficient provides evidence for coupling between proton abstraction and leaving group expulsion; it confirms the concerted AxhDHDN (E2) mechanism. The values of β and βlg indicate an imbalance in the transition state, in which proton transfer is ahead of leaving group expulsion. The change from a stepwise AxhDHH+DNN (ElcB) mechanism for thiophenoxide leaving groups to a concerted mechanism for sulfide leaving groups is consistent with the notion that the mechanism is determined solely by the lifetime of the carbanion; there is no evidence for the coexistence of stepwise and concerted mechanisms.
