Zinc trifluoromethanesulfinate

Wallace, J. W Gimpel, H. E. In Handbook of Petroleum Refining Processes, Meyers, R. A., Ed. McGraw-Hill New York, 1997. 

Yoshihiro Ishihara, Ryan Gianatassio, Phil S. Baran The Scripps Research Institute, La Jolla, CA, USA 

Alternative Names his((trifluoromethanesulfinyl)oxy)zinc, (CF3S02)2Zn, TFMS 

Solubility soluble in H2O, DMSO, MeOH, EtOH, acetone, and MeCN partially soluble in EtOAc insoluble in CH2CI2, CHCI3, CICH2CH2CI, toluene, perfluorotoluene, and anisole. 

Form Supplied in off-white powder. In its purest form, it is most likely a cUhydrate. When preparing zinc trifluoromethanesulfinate (TFMS), common impurities are Zn, ZnCl2, and H2O Zn 

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Heteroarene Functionalization One-pot Sequential Functionalization Chemistry. Zinc isopropylsuUinate can be considered as a radical with nucleophilic character. Zinc trifluoromethanesulfinate (TFMS), another zinc bis(alkanesulfinate) reagent, possesses a rather electrophilic character. By taking advantage of the electrophiUcity/ nucleophiUcity of the reactive radical species, a one-pot sequential functionalization reaction was developed. Dihydroquinine can undergo tandem trifluoromethylation and isopropylation without the need for secondary alcohol protection (eq 7). 

Introduction. Zinc trifluoromethanesulfinate (TFMS) is a commercially available reagent that appends trifluoromethyl units to heteroarenes under practical and mild conditions. Reaction temperatures range between room temperature (rt) and 50 °C, the reaction is tolerant of air and moisture, and the reaction solvent can be H2O or even unconventional media such as tea or cell lysate. Innately reactive positions of a heteroarene undergo the transformation of carbon-hydrogen to carbon-trifluoromethyl. C-H functionalization of innate positions and methods to override this inherent reactivity, as well as one-pot sequential functionalizations of two different positions of a heteroarene will be discussed herein. 

This condensation with sulfur dioxide is rather peculiar. To the difference with carbonyl electrophiles, sulfur dioxide is more easily reduced than trifluoromethyl bromide. As already pointed out, initial consumption of zinc by this anhydride was obvious, producing the sulfoxylate radical anion which is known to be in equilibrium with the dithionite anion (Fig. 15). Incidentally, this salt mixed with sodium bicarbonate in aqueous acetonitrile was used for the transformation of liquid perhalogenoalkyl halides into their corresponding sulfmates (ref. 24). We have been able to transform the gaseous and poorly reactive trifluoromethyl bromide into sodium trifluoromethanesulfinate. However, the reaction conditions (Fig. 16) (ref. 25) were modified because no transformation occurred in the medium employed for the sulfinato-dehalogenation of the liquid halides. 

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