Process for producing disubstituted 4-hydroxycyclopentenones; monosubstituted cyclopentendiones and 4-hydroxycyclopentenones.

摘要

A method of producing a 4-hydroxycyclopentenone rep resented by the formula,
<Chemistry id="chema01" num="0001"><Image id="ia01" he="17" wi="33" file="IMGA0001.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>wherein R, is an alkyl, alkenyl, alkynyl, cycloalkyl, thienyl, phenyl, p-methylbenzyl or benzyl group and R<Sub>2</Sub> is an alkyl, alkenyl or alkynyl group having 6 or less carbon atom, which comprises reacting a furylcarbinol compound of the formula,
<Chemistry id="chema02" num="0002"><Image id="ia02" he="12" wi="36" file="IMGA0002.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>wherein R, is as defined above, in the presence of an acid in a mixed solvent of water and an organic solvent, to obtain a cyclopentenone compound of the formula,
<Chemistry id="chema03" num="0003"><Image id="ia03" he="21" wi="31" file="IMGA0003.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>wherein R is as defined above; reacting the cyclopentenone compound in the presence of an oxidizing agent to obtain a cyclopentendione compound of the formula.
<Chemistry id="chema04" num="0004"><Image id="ia04" he="16" wi="38" file="IMGA0004.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>wherein R, is as defined above; reacting the cyclopentendione compound with a Grignard reagent of the formula,
<Sup>R</Sup><Sub>2</Sub>MgX wherein R<Sub>2</Sub> is as defined above and X is chlorine, bromine or iodine atom, to obtain an oxocyclopentene compound of the formula,
<Chemistry id="chema05" num="0005"><Image id="ia05" he="17" wi="28" file="IMGA0005.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>wherein R<Sub>1</Sub> and R<Sub>2</Sub> are as defined above; and reacting the cyclopentenone compound in the presence of a base.

The 4-hydroxycyclopentenones are useful intermediates of agricultural chemicals.