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The products were characterized by spectral and analytical means as summarized in the table. This reaction represents a general, simple, mild, and superior procedure for the direct synthesis of a variety of isopropylidene diarylmalonates 3 and isopropylidene alkylarylmalonates 5. Furthermore, since substituted isopropylidene malonates are readily hydrolyzed to carboxylic acids12 or converted to esters,13 this method represents an indirect, efficient preparation of -aryl carboxylic acids or their esters. Experimental SectionAll melt) ig points are uncorrected. NMR spectra were recorded at 60 MHz on a Varían EM-360 spectrometer with Me4Si in CDC13 as the internal standard, and IR spectra were recorded on a PE-683 spectrometer.Starting Materials. Meldrum's is commercially available or can be readily made by condensation of malonic acid with acetone. The necessary diaryliodonium salts 2 were prepared by standard procedures according to Beringer and co-workers.14 General Procedure for the Preparations of 3 and 5. Potassium metal (0.78 g, 20 mmol) was added to 20 mL of anhydrous tert-butyl alcohol. After reaction, 1.44 g (10 mmol) of Meldrum's acid (1) was added under nitrogen at 70 °C. To this solution was slowly added 20 mmol of the appropriate diaryliodonium salt 2. (For reaction of 4 with 2 the molar ratio of K to 4 to 2 was 1:1:1.) The resulting solution was stirred at 70 °C for several hours (see Table I) until it turned clear. After cooling, the solvent was removed, and to the residue were added 30 mL of methylene chloride and 10 mL of water. The organic layer was separated, washed successively with 10 mL of water, 10 mL of 5% aqueous NaHCOa, and 10 mL of water, and then dried over anhydrous MgS04. The methylene chloride was removed, to the residue was added 20 mL of petroleum ether, and the mixture was allowed to stand in a refrigerator overnight. The resulting crystals were collected by suction filtration and purified by recrystallization from benzene/hexane. All relevant data are summarized in the table.

fashion to that described above, to provide a hydrocarbon (0.32 g, 73%). On GLC analysis the mixture was found to contain two components with retention times of 18.91 and 19.55 min in the ratio 21.2:78.8 (column A; oven temperature 100 °C, 10 min-5°/min-250 °C), respectively. From GC/MS data and the 13C NMR (CDC13) spectrum, the oil was found to contain the less symmetrical alkene as the minor component (15-20%) and the more symmetrical alkene as the major isomer. 8]tetradec-4-ene:

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