Zinc isopropylsulfinate

Alternative Names zinc 2-propanesulflnate, bis((isopropyl-sulfinyl)oxy)zinc, (i-PrS02)2Zn, IPS. 

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

Form Supplied in pearly white powder. In its purest form, it is most likely a dihydrate. When preparing zinc isopropylsulfinate (IPS), common impurities are Zn, ZnCl2, and H2O Zn is used in excess when preparing IPS, ZnCl2 is a stoichiometric by-product, and H2 O is the solvent. The commercially available IPS may contain ZnCl2 and H2O, but these impurities do not adversely affect the reaction because it is typically mn under aqueous (or compatible with H2O) and acidic conditions. 

Analysis of Reagent Purity IPS has been characterized by elemental analysis, IR, and and NMR.  

Handling, Storage, and Precautions zinc isopropylsulfinate is stable to ambient-temperature storage under air and no particular precautions need to be taken when handling this compound. 

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Introduction. Zinc isopropylsulfinate (IPS) is a commercially available reagent that appends isopropyl units to heteroarenes under practical and mild conditions. Reactions are run at either room temperature (rt) or 50 °C, the reaction is tolerant of air and moisture, and the reaction solvent can even he H2O. Innately reactive (i.e., electrophihc) positions of a heteroarene undergo the transformation of carbon-hydrogen to carhon-isopropyl. C-H functionalization of these innate positions and methods to override this inherent reactivity as well as one-pot sequential functionalization of two different positions of a heteroarene wiU he discussed herein. 

Heteroarene Functionalization Innate Functionalization of Simple Systems. Zinc isopropylsulfinate can functionalize heteroarenes in one step under oxidizing conditions (using TBHP) to add steric hulk and lipophilicity where desired. Since the innate reactivity of the heterocyclic substrate dictates the regiochemistry of the product, the regioselectivity is good for some substrates (eq 2) but is poor for others (eq 3). Furthermore, the isopropyl substituent can serve as an activating group for pyridine substrates, and therefore polysubstitution can occur. ... 

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