While comparing analogousp olystyrenesupported and homogeneous catalysts for the Baylis-Hillmanr eaction, we hypothesized that the hydrophobice nvelopment of the imidazole catalytic sites of the former is responsible for the significantly better chemoselectivity exhibited by the heterogeneous catalysts compared to theirh omogeneousc ounterparts.I no rder to test this hypothesis,w ep repared as eries of branched/dendritic homogeneousc atalysts,w ith an imidazole active site near the focal point andf lexiblet ails of various lengthsa nd polarities,c apable of providing partials hieldingo ft his site.T he design of the catalysts was based on a5 -hydroxyisophthalate scaffold,a nd they were prepared throughanumber of multistep synthetic pathways. Thec omparison of the catalysts under av arietyo f conditions in am odel Baylis-Hillman reactiond emonstrated that long hydrophobic tales enhance the chemoselectivity parameter of the catalysis,w hile reducing the rate of the consumptiono ft he substrates, and that the chemoselectivity is further improvedb y the presence of af ree phenolic moiety in the vicinity of the catalytic imidazole unit. Moreover, in secondgeneration catalysts,t he peripherall ong tails could be either hydrophobic or polar, since the dendritic inner backbone itself presumably partially provides the necessary isolation of the catalytic site.T hus,e xperimental results support our hypothesis.Synthesis of 1,3-bis(methoxymethyl)-5-(methoxymethoxy)benzene: Thec ompound was prepared according to the typical procedure for the benzylic alcohol alkylation, using the followingq uantities:i odomethane (1.68 mL, 28.0 mmol, 4.0 equiv.), [5-(methoxymethoxy)-1,3-phenylene]dimethanol