Maitland-Japp synthesis

The Maitland-Japp synthesis of highly substituted tetrahydropyran-4-ones152a (e.g. 

Substituted tetrahydropyrans are key structural fragments in numerous natural products, and this has prompted much research into their synthesis. Among the many known methods, we will focus on the Maitland-Japp reaction and its modernization... 

Scheme 3.15 Clarke s one-pot, four-component synthesis of tetrahydropyrans by a modified Maitland-Japp reaction.

Iqbal, M., Mistry, N., Clarke, P. A. (2011). An asymmetric Maitland-Japp reaction a highly enantioselective synthesis of tetrahydropyran-4-ones. Tetrahedron, 67,4960-4966. 

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