4-Chlororesorcinol → 2',4,5,6,7,7'-hexachloro-3',6'-dihydroxy-3H-spiro[isobenzofuran-1,9'-xanthen]-3-one

Participants

Reaction Steps

Treatment of tetrachlorophthalic anhydride (5 g, 17.49 mmol) and 4-chlororesorcinol (6.32 g, 43.73 mmol), according to the procedure described in Example 1 Step 1, provided 10.31 g of crude product. Suspension of a 9.25 g portion of this in DMF:water (1:1) followed by filtration, provided 9.70 g (2:1 DMF complex 17.16 mmol, 92.3% yield) of 2′,4,5,6,7,7′-hexachloro-3′,6′-dihydroxy-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one that was isolated as an orange solid. 1H NMR (300 MHz; DMSO d6) δ 11.13 (S, 2H), 7.31 (s, 2H), 6.89 (s, 2H).

Provenance & Evidence