Triphenylphosphine, reduction ozonides

The bicyclic ozonides 12 23) and thiaozonides 13 2S) afford on catalytic hydrogenation (Pd-C) the expected 1,4-diones 61 (Eq. 47). Alternatively, deoxygenation of 12 or desulfurization of 13 with triphenylphosphine led to the same products essentially quantitatively. Both reductions served for the chemical characterization of these... 

The ozonides of choline and ethanolamine phosphatides and triglycerides can be subjected to reduction with triphenylphosphine to yield the corresponding core aldehydes, and further derivatized to the 2,4-dinitrophenylhydrazones (DNP). The core aldehydes and their DNP derivatives can be separated by HPLC and characterized by various techniques, including EI-MS and TS-MS of positive and negative ions . See also Section VHI.E. 

The deoxygenation of epoxides is not of great preparative value since it involves some loss of stereochemical integrity and the alkenes produced are more readily approached in other ways. Reductive cleavage of ozonides, for example, using triphenylphosphine, commonly forms part of the ozonolysis procedure for conversion of alkenes into carbonyl compounds. If a carbonyl compound is treated with an appropriate P(III) reagent then the reverse process may occur—reductive coupling to form a new C=C double bond. This has found a particularly important... 

The reduction of ozonides with triphenylphosphine,113 on the other hand, proceeds quantitatively with both ketozonides and aldozonides. Lorenz102,112 used this reaction as the basis of a method for the determination of ozonides. The reaction mechanism is probably as shown in Eq. (8).102... 

Reduction of ozonides [1, 1244, after citation of ref. 23]. Pappas et al.2Sa found triphenylphosphine the most satisfactory reducing agent for ozonides derived from nephthalenic compounds. 

Phosphines and phosphites are readily oxidized by ozone (81). The 1 1 adducts have pentacovalent phosphorus structures (82). Ozonides are reductively cleaved by triphenylphosphine (83). 

PI3 can be used for the efficient reduction of an ozonide, as illustrated by the formation of the cyclopropanecarbaldehyde in eq advantage over the traditional Triphenylphosphine... 

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