Lemieux-von Rudloff

See also the Lemieux-von Rudloff Reagent, where catalytic KMn04 is used in place of 0s04 ... 

Fig. 17.29. The Ru04 cleavage of a phenyl ring is exemplified by the case of an altylated aromatic compound using the modified Lemieux-von Rudloff conditions (Figure 17.26). The reaction involves three key intermediates the cr-ketoalde-hyde A, the a-keto acid E, and the ruthenium(VIII) acid diester G. It is unclear how the reaction of E —> G proceeds. In the last step, G undergoes a fragmentation via a cyclic transition state and forms a substituted acetic acid I, Ru03 and carbon dioxide.

A mixture of potassium permanganate and sodium periodate has also been used to cleave double bonds. This procedure, usually referred to as the Lemieux-von Rudloff reaction, can be carried out in several mixed solvent systems such as butanol and water, dioxane and water " or acetone and water. " It has also been claimed that the addition of phase transfer agents improves yields. 

S-8-S carbon skeleton of Aisicoccins and ophiobolins (equation 10). Trisubstituted alkenes yield keto acids (equation 11). A related reaction, known as the Lemieux-von Rudloff (periodate-permanganate) oxidation, is also used to oxidize alkenes to acids or ketones (equation 12). If aldehydes are required... 

Li et al. developed a simple and versatile strategy for converting hydrophobic rare earth nanophosphors into water-soluble and carboxylic acid-functionalized analogues. The surface oleic acid ligands could be directly oxidized by the Lemieux-von Rudloff reagent, and the modified NCs kept the excellent luminescence and were further used as DNA labels (Figure 77) (Chen et al., 2008c). 

Figure 1339 Surface ligand oxidation strategy for synthesis of functionalized oleic acid-capped UCNPs. (a) Direct oxidization with the Lemieux-von Rudloff reagent and (b) epoxidation and further coupling with mPEG-OH.

In order to introduce an (z-glycol moiety at positions 5 and 6, pregnenolone acetate (234) was treated with the Lemieux-von Rudloff reagent. Instead of the expected glycol, a mixture of 5, 6)3-epoxide (235), triol (236), and diol (237)... 

Periodate-Permanganate oxidation [1, 810-812, at end]. In carrying out the oxidation of (R)-(+)-citronellol (8) to the 6-hydroxy-4-methylhexanoic acid (9) by the Lemieux-von Rudloff reagent, Overberger and Kaye16 used acetone-water as the medium in order to conduct the oxidation at a higher concentration. 

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