PURPOSE: To obtain a cyclic acetal which itself exerts a good herbicidal effect and is useful as an intermediate for preparation of a substituted salicylic acid derivative having a good herbicidal effect and/or bioregulatory activity.
CONSTITUTION: This compound is a compound of formula I (wherein R1 and R2 are each H, alkyl or phenyl, or R1 and R2 together form 3-6C alkylene; Y is O or S; A is A1-A6; A1 is OH; A2 is halogen, alkylsulfonyloxy, fluorosulfonyl or the like; A3 is CN, NO2 or formyl; A4 is phenyl, a 5-6 membered heterocyclic ring having four or less hetero atoms, naphthyl or the like; A5 is alkenyl, cycloalkenyl, cycloalkadienyl or the like which optionally has seven or less substituents; and A6 is alkyl or cycloalkyl which optionally has seven or more substituents), e.g. 5-hydroxy-2,2-dimethyl-4H-(1,3)benzodioxin-4-one. A compound of formula I wherein A is A1-A3 is obtained by allowing a 6- hydroxy- or 6-mercaptobenzoic acid of formula II to react with a compound of the formula, O=CR1R2 in the presence of an acid catalyst.
RHEINHEIMER JOACHIM (DE)
VOGELBACHER UWE JOSEF (DE)
BAUMANN ERNST (DE)
KOENIG HARTMANNN (DE)
GERBER MATTHIAS (DE)
WESTPHALEN KARL-OTTO (DE)
