One-Pot Synthesis of β-Phosphonomalonates Catalyzed by Molecular Iodine

Abstract

A one-pot procedure has been developed for the synthesis of β-phosphonomalonates via P-C bond formation through tandem Knoevenagel–phospha–Michael reaction catalyzed by iodine as a new, inexpensive, nonmetallic, and commercially available catalyst.

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GRAPHICAL ABSTRACT

Keywords:

• Iodine
• malononitrile
• phosphites
• β-phosphonomalonates
• tandem reaction

ACKNOWLEDGMENT

We are thankful for all the support we received from the University of Birjand Research Council.

Notes

^a Isolated yield. Conditions: aldehyde (1 mmol), malononitrile (1 mmol), triethyl phosphite (1 mmol).

^a Isolated yield. Conditions: aldehyde (1 mmol), malononitrile (1 mmol), triethyl phosphite (1 mmol), iodine (10 mol%), 50 °C, solvent-free conditions. All the products were characterized by spectroscopic methods and compared with the authentic spectra.

^a Isolated yield. 4-Chlorobenzaldehyde (1 mmol), active methylene group (1 mmol), trialkyl phosphite (1 mmol), catalyst (10 mol %), 50 °C, solvent-free conditions. All the products were characterized by spectroscopic methods and compared with the authentic spectra.

^a Isolated yield. Conditions: catalyst (10 mol%), benzaldehyde (1 mmol), malononitrile (1 mmol), triethyl phosphite, 50 °C, solvent free.

^a Isolated yield. Conditions: catalyst (10 mol%), salicylaldehyde (1 mmol), active methylene group (1 mmol), triethyl phosphite, 50 °C, solvent free.