SO₂F₂-promoted Thiocyanation And Iodization （Bromination） Of Alcohols

Organic thiocyanates and halides compounds are versatile intermediates in organic synthesis and widely used in the synthesis of pharmaceuticals,dyes,natural products,agrochemicals,as well as biologically active molecules.The favorable physiochemical profile and chemical stability combine to propel organic thiocyanates and halides compounds to the forefront of functional groups employed in the design of modern bioactive molecules.Furthermore,organic halides are often used in the C-C bond formation via radical or substitution reactions and they serve as intermediates in a wide variety of reactions and rearrangements.In the past decades,there have been many strategies to obtain the alkyl thiocyanates and halides.The reported procedures suffer from one or the other drawbacks such as low yields,long reaction times,drastic reaction conditions and tedious work-up procedure.Based on previous work,we have been developed SO₂F₂-promoted thiocyanation and iodization（bromination）of alcohols which is cheap and readily available.The main contents are as follows:1、SO₂F₂-promoted thiocyanation of alcoholsA novel SO₂F₂-promoted thiocyanation of alcohols was developed.The reaction conditions for the alcohols to thiocyanates consisted of Na₂CO₃（4.0 equiv.）,NH₄SCN（1.0 equiv.）,Et OAc（2.0 m L）was stirred at room temperature under SO₂F₂ atmosphere（SO₂F₂ balloon）for 5h.A wide range of alcohols underwent this transformation,producing the corresponding alkyl thiocyanates in modest to high yields,demonstrating the great functional groups compatibility and high efficiency of this new protocol.In addition,the reaction can be readily conducted on a gram scale in excellent yield,which performed to demonstrate the applicability of thiocyanates.2、SO₂F₂-promoted iodization（bromination）of alcoholsThe study expanded the application of SO₂F₂ as a promoter in nucleophilic substitution of alcohols.The reaction conditions consisted of Na₂CO₃（1.0 equiv.）,NH₄I（Br）（1.0 equiv.）,CH₃CN（2.0 m L）was stirred at room temperature under SO₂F₂atmosphere（SO₂F₂ balloon）for 4h,Which provide corresponding products with yields up to 74-97%.This system features good functional group tolerance,broad substrates and high efficiency.Moreover,the reaction can be easily carried out in grams with excellent yield,which proved to the applicability of iodization（bromination）.