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Bis(pyridodipyrimidines) (bis-PP's) as redox catalysts, in which two pyridodipyrimidine moieties are linked with polymethylene chains, have been synthesized by the condensation of bis(6-chloro-5-formyluracil-3-yl)alkanes with 6-alkylaminouracils. These bis-PP's oxidized alcohols more efficiently than monomeric pyridodipyrimidines to give the corresponding carbonyl compounds. Particularly, bis(7-methyl-10-(/i-octyl)pyridodipyrimidin-3-yl)decane (5j) exhibited remarkable oxidizing ability toward cyclopentanol as a turnover catalyst, and its maximum effective concentration (MEC) was determined. The MEC of 5j was 6.7 X 10~5 mmol (59 Mg)/3 mL of cyclopentanol at 115 °C, and the MEC under introduction of oxygen (5 mL of oxygen/min) was 2 X 10"4 mmol (177 Mg)/3 mL of cyclopentanol at 100 °C. Apart from the chemical yield of cyclopentanone, even an amount of only 2 X 10"11 mmol (17.7 pg) of catalyst 5j oxidized cyclopentanol to give cyclopentanone in 13300000000000% yield based on the catalyst. This implies that the turnover number of catalyst 5j is 8.9 X 107 mol min"1 (mol of catalyst)"1, which would surpass that of bovine liver catalase, although the condition is quite different.Pyridodipyrimidines (1) as new NAD-type redox catalysts have been found to oxidize a variety of alcohols under neutral conditions to yield the corresponding carbonyl compounds, and a considerably high autorecycling turnover in the oxidation was observed.1 In order to obtain more efficient redox organic catalysts, we have planned to manipulate the above oxidizing ability in terms of the linking of two pyridodipyrimidine moieties with polymethylene chains. Such linked bis(pyridodipyrimidine) (bis-PP) derivatives

As a typical example, cyclopentanol was used because of its stability toward t3-Methyl-6-stearylaminouracil was prepared by the condensation of 6chloro-air oxidation.3-methyluracil and stearylamine under refluxing in n-butanol for 5 h.

Condensation of bis(3‐methyluracil‐6‐ylamino)alkanes with 6‐chloro‐5‐formyl‐3‐methyluracil or 2,4,6‐trichloropyrimidine‐5‐carbaldehyde in acetic acid gave the respective bis(pyridodipyrimidin‐10‐yl)alkanes (vertical‐type bis(pyridodipyrimidines)). The vertical‐type bis(pyridodipyrimidines) exhibited autorecycling turnover oxidation toward cyclopentanol and l‐menthol to give the corresponding carbonyl compounds.