Compounds of the present invention are represented by the formula, ##STR1## wherein X represents a lower alkyl, lower alkoxy, lower haloalkyl or lower haloalkoxy group or a halogen atom, and R.sup.1 and R.sup.2, which may be the same or different, represent a hydrogen atom or a methyl group. They are useful intermediates for preparing herbicidal compounds.
An environmentally benign and highly efficient supramolecular Michael addition of thiols from the secondary side of beta-cyclodextrin to alpha,beta-unsaturated compounds at the primary side in water is described in quantitative yields; products of undesirable side reactions resulting from polymerization are not observed; the use of cyclodextrin precludes the use of either acid or base and the catalyst