Regioselective synthesis of 4-(2-oxoalkyl) pyridines via 1, 4-dihydro-pyridine derivatives using silyl enol ethers and pyridinium salts

~%

~52%

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~69%

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~10%

~35%

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~21%

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~6%

~31%

~66%

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~%

~40%

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~64%

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