Tandem oxidation-cyclocondensation

Hydroxylations of fatty acids by cytochrome P450119 compound increase in rate with chain length and show no intermolecular KE in buffer. With glycerol, the rate of reaction of lauric acid increases, and a KIE is observed. Reversible formation of a non-reactive complex of a fatty acid with the cytochrome and its isomerization to a reactive one is proposed. A tandem oxidative cyclocondensation process is reported for the synthesis of 3,4-dihydropyrimidin-2(l//)-one or -thione derivatives from primary aryl alcohols, -keto esters, and urea or thiourea in the presence of aluminium nitrate nonahydrate as oxidant catalyst. ... 

The oxacycles have remained a more challenging synthetic task as compared to the N- and S-containing medium sized rings. The medium sized lactones have also attracted significant attention as these are considered to be a rare class of organic compounds, which are even difficult to produce in natural biosynthetic pathways (Shiina, 2007). Bagley et al. (2009) reported microwave-assisted synthesis of seven membered lactones through a tandem oxidation- cyclocondensation of 1,6-hexane-diol. 

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