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All articles of this category 4-Hydroxycoumarins (4-hydroxy-2-oxo-2 H -1-benzopyrans) were synthesized in good to excellent yields by C-carbonylation of 2′-hydroxyacetophenones with carbon monoxide in the presence of sulfur and bases. This is the first example of sulfur-assisted C-Carbonylation with carbon monoxide.
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Mizuno et al. (1988) studied this question.
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