Pfitzner-Moffatt reagent

Equimolar quantities of benzhydrol and the phosphorane (3a) were also reacted in dimethyl sulphoxide solution. Apart from bis(benzhydryl) ether (18%) and catechol monobenzhydryl ether (39%), a small amount of benzophenone (17%) was obtained. It was shown that, in the absence of phosphorane, benzhydrol is not oxidised to benzophenone by dimethyl sulphoxide. Reaction similar to that outlined in Scheme 1 is a likely possibility. Again, the alcohol is activated by reaction with the phosphorane toward nucleophilic attack, in this case by dimethyl sulphoxide. Significantly, oxidation of alcohols by dimethyl sulphoxide is usually carried out using the Pfitzner-Moffatt reagent (dicyclohexyl carbodiimide and anhydrous phosphoric acid in dimethyl sulphoxide) (13) whereas the reaction using the phosphorane (3a) is carried out under neutral conditions. Unfortunately, however, attempts to improve the yield of benzophenone have hitherto failed. 

Grob fragmentation.1 The combination of these reagents cleaves cyclic y-tri-butylstannyl alcohols at 25° in CH2C12 to unsaturated aldehydes and ketones.2 The actual reagent is considered to be 1, a modified Pfitzner-Moffatt reagent, which converts the substrate into an iodine(III) intermediate. 

Brimacombe, J S, Bryan, J G H, Husain, A, Stacey, M, Tolley, M S, The oxidation of some carbohydrate derivatives, using acid anhydride-methyl sulphoxide mixtures and the Pfitzner-Moffatt reagent. Facile synthesis of 3-acetamido-3-deoxy-D-glucose and 3-amino-3-deoxy-D-xylose,... 

The Pfitzner-Moffatt reagent was found to provide the best method for oxidation... 

Reaction of cholesterol with the reagent gives as the major product the methyl thiomethyl ether.43d The Pfitzner-Moffatt reagent gives A1-cholestenone.43d... 

However, the preferred route is oxidation of (4) by the Pfitzner-MofFatt reagent followed by Baeyer-Villiger reaction. 

Oxidation of hydroxy steroids. Hydroxy steroids are oxidized to keto steroids in about 60% yield by the combination of N,N-diethyl-l-propynylamine-DMSO catalyzed by phosphoric acid. Benzene is used as solvent.1 In later work2 the combination of diphenylketene-p-tolylimine and DMSO was used with somewhat improved yields (compare Pfitzner-Moffatt reagent). 

Actually, the direct oxidation of (I) to (2) can be carried out in 81% yield with (he Pfitzner-Moffatt reagent (DMSO, DCC, and H3P04).15... 

In a total synthesis of the alkaloid di-camptothecin, Rapoport et al. investigated the oxidation of the alcohol (1). The Pfitzner-Moffatt reagent proved... 

The Pfitzner-Moffatt reagent was also shown to be effective for oxidation of the related alcohol (3) to the corresponding ketone (76% yield). 

Oxidation of an allylic alcohol. This reagent has been used successfully to oxidize the benzyl ester of the /S-lactam antibiotic clavulanic acid (1) to the labile allylic aldehyde 2. Attempted oxidation with the Pfitzner-Moffatt reagent resulted in formation of a 1,3-diene by a 1,4-elimination. ... 

The liquid-phase oxidation of 1,3-dithian, and oxidation of alcoholic functional groups in the presence of the 1,3-dithian moiety by the Pfitzner-Moffatt reagent, has been studied. Both cis- and 1,3-dithian 1-A -arylimides (167) were prepared and they rearranged with high stereospecificity. 1,3-Dithian 1-imide 1,3,3-trioxide (168) has been obtained, in excellent yield, by the cleavage of the corresponding A-tosyl compound with Na and... 

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