Tetrapropylammonium perruthenate TPAP

Hydroboration occurred from the less hindered top face of rac-29 and resulted in the formation of alcohol rac-30. After a three-step sequence which included oxidation with tetrapropylammonium perruthenate (TPAP), methyl lithium addition and repeated oxidation with TPAP, ketone rac-31 was isolated. Finally, epimerization of the stereogenic center at C-7 to the correct configuration and methylenation with the Lombardo reagent led to the formation of racemic kelsoene (rac-1). 

Reductive alkylation of -caprolactone (1 equiv) with a 2 0.25 mixture of Grignard reagent and Zn(BH4)2 affords monoalkylated diols, which can be further selectively oxidized with tetrapropylammonium perruthenate (TPAP) into the expected monoalkylated lactones <2002CR571>. 

Griffith, W. P., Ley, S. V., Whitcombe, G. P., White, A. D. Preparation and use of tetrabutylammonium perruthenate (TBAP reagent) and tetrapropylammonium perruthenate (TPAP reagent) as new catalytic oxidants for alcohols. J. Chem. Soc., Chem. Common. 1987,1625-1627. 

Tetrapropylammonium perruthenate (TPAP 63 mg) was added in 1 portion to a stirred mixture of A -Boc-4-fra .y-hydroxy-L-proline (1 g, 3.47 mmol), A-methyl-morpholine A-oxide (0.62 g, 15.6 mmol), and powdered molecular sieves (4 A, 1.78 g) in CH2CI2 (7 mL) at room temperature under argon. The mixture was stirred for 3 h, filtered, and evaporated in vacuo to give a black residue. The product was purified by... 

Scheme 15). Treatment of 42 with DDQ in CH2CI2/H2O (19/1) afforded diol 43 in 81% yield. Subsequent oxidation was carried out with a catalytic amount of tetrapropylammonium perruthenate (TPAP) and N-methylmorpholine-Y-oxide to furnish lactone 44 in 82% yield.In the H NMR spectrum of 44, the coupling constants of Jl,l-trans, and... 

As a further extension, the Kim group very recently developed the aerobic oxidation and [l,5]-hydride transfer/cyclization sequence starting from readily available ortho tertiary amine substituted cinnamyl alcohols 24 (Scheme 4.12). The tetrapropylammonium perruthenate (TPAP) was identified as the competent catalyst for the initial aerobic oxidation of the allylic alcohols. The synthetically useful tetrahydroquinoline derivatives 25 were prepared in moderate yields and high level of enantioselectivity. 

Oxidative isomerization of vinylidenecyclopropanes gives dimethylenecyclopropane aldehydes using tetrapropylammonium perruthenate (TPAP)/4-methylmorpholine A-oxide (NMO) as a catalytic system. A Witkop-Winterfeldt oxidation with ozone has been reported to convert tetrahydropyridoindoles into pyrroloquinolones and cinnolines. Activation of phenol derivatives with a hypervalent iodine reagent has been reported to promote the formation of bicycUc and tricyclic products via a cationic cyclization process (Scheme 64). ... 

The oxidation of alcohols with (l,l-dimethylethyl)benzene-sulfenamide is extremely mild and many sensitive functional groups such as epoxides and alkenes are tolerated hy the reaction conditions (eq 5). In the case of alcohol 1, oxidation with tetrapropylammonium perruthenate (TPAP) resulted in only 58% yield and Swern oxidation was unsuccessful. Epimerizable aldehydes such as the protected phenylglycinol 2 do not undergo racemization when oxidized (eq 6). ... 

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