A Facile, Selective Preparation of Monoketals from Pentaerythritol and Ketones

Abstract

The selective preparation of monoketals 3a-f from pentaerythritol 1 and cyclic, acyclic, aromatic, and aliphatic ketones 2a-f was achieved by a facile method. The extreme polarity and low solubility of pentaerythritol in almost all organic solvents were the main difficulties to be overcome for the preparation of monoketals in good yields and high selectivity. A benzene-dimethylformamide (40:60) mixture proved to be excellent for the ketalization. The one-step procedure developed allowed the preparation of monoketals in good yields and good to excellent selectivity (higher than 90%).

Key words

pentaerythritol - 1,3-diols - monoketals - monoprotection - 1,3-dioxanes

References

• 1a

  Research Assistant from CONICET

• 1b

  Research Assistant from U. N. L

• 1c

  Professor at U. N. L. and Member of CONICET’s Research Staff

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