TPAP

Tetra-n-propylammoniurn Perruthenate (TPAP, nPr4N+ Ru04")... 

Tetra-n-propylammonium perruthenate (TPAP, tetrapropyl tetraoxoruthenate) [114615-82-6] M 351.4, m 160"(dec). It is a strong oxidant and may explode on heating. It can be washed with aq n-propanol, then H2O and dried over KOH in a vac. It is stable at room temp but best stored in a refrigerator. It is sol in CH2CI2 and MeCN. [Dengel et al. Transition Met Chem 10 98 1985 Griffith et al. J Chem Soc, Chem Commun 1625 1987.] Polymer supported reagent is available commercially. 

Nicolaou and co-workers established the severely strained A-ring oxazole (21) in their total synthesis of antitumor agent diazonamide A through initial oxidation of the hindered alcohol of intermediate 20 with TPAP and subsequent Robinson-Gabriel cyclodehydration of the resultant ketoamide with a mixture of POCI3 and pyridine (1 2) at 70°C. ... 

Whereas treatment of ( )-29 with camphanic chloride achieves the selective esterification of the hindered C-9 hydroxyl group, the action of acetic anhydride on (+)- 29 results in the equally selective acetylation of the C-10 hydroxyl group It is not clear to what this discrepancy should be attributed, so we will not offer a rationalization here. This unexpected result is, however, most gratifying because TPAP-NMO oxidation27 of the remaining C-9 hydroxyl furnishes keto acetate 6 (88 % overall yield). You will note that the contiguous keto and acetate functions in 6 are both expressed in the natural product. 

Because of the strongly basic conditions needed for Wittig reactions with now-stabilized ylides, one-pot reactions have not been carried out [57]. Ley s recent report of a TPAP-Wittig oxidation performed in a sequential one-pot manner is thus a promising alternative [58]. The reaction is fast and straightforward the... 

Primary and secondary aliphatic nitro compounds have been oxidized to aldehydes and ketones, respectively (RR CHN02 RR C=0) with sodium chlorite under phase-transfer conditions, TPAP, Oxone , as well as with other reagents. 

Woo et al. [54] prepared new chiral tetraaza macrocyclic hgands (48 in Scheme 23) and their corresponding iron(II) complexes and tested them, as well as chiral iron(II) porphyrin complexes such as Fe (D4 -TpAP) 49, in asymmetric cyclopropanation of styrene. 

The adduct cyclized to a lactol mixture that was oxidized by TPAP-NMMO to give the corresponding lactones in an 8 1 ratio (86% yield). Hydrolysis in the presence of H202 gave the P-D lactone and recovered chiral auxiliary. 

A very mild oxidative transformation of nitro compounds into ketones using tetrapropylam-monium perruthenate (TPAP) has been developed. A stoichiometric amount of TPAP in the presence of A-methylmorpholine A-oxide (NMO) and 4 A molecular sieves (MS).18a As the reaction conditions are neutral and mild, this method is compatible with the presence of other sensitive functionalities (Eq. 6.11). This transformation can be carried out with 10 mol% of TPAP and 1.5 equiv of NMO in the presence of potassium carbonate, 4 A MS, and silver acetate (Eq. 6.12).18b... 

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