While the direct, one-step conversion of meso-tetrakis(pentafluorophenyl)porphyrin to its corresponding bacteriodilactone is well established, no such reaction has been achieved for meso-tetraphenyl or meso-tetrakis(4-trifluoromethylphenyl)porphyrin. Thus, we describe two stepwise oxidation approaches of these porphyrins toward the corresponding bacteriodilactones, as mixtures of two inseparable regioisomers. As [ ‡] Oxazolochlorins. 475shown by 1 H NMR spectroscopy, the ratio of the two isomers is oxidant-dependent. Their Zn II and Pd II complexes were formed by metal ion insertion into the free bases. Some of the free base dilactones and their metal complexes were also characterized crystallographically, demonstrating the planarity of the macrocycle. This report makes these intriguing porphyrinoids synthetically accessible for further study. Full Paperlactone analogues of the carbaporphyrins, [20] subporphyrin, [21] dithiaporphyrin, [22] and hydroporphyrins. [19,23] Since their discovery in 1984, [24] a number of oxidative pathways were described that generated porpholactones from various ( -substituted) porphyrins and chlorins. [2c,3,4,17a,25] In fact, porpholactones appear to be a common -and frequently adventitious -product when the -positions of meso-arylporphyrins are being manipulated under oxidizing conditions. [4,24,25c,26] This is remarkable in as much as there is no known precedent for the formation of porpholactones in nature as part of the degradation pathways of the naturally occurring -alkyl-porphyrins and -chlorins. [27] Among the synthesis pathways toward porpholactones, the direct, one-step oxidation of a non-activated porphyrin is an attractive option. [25a,25b,25d,28] It is possible to oxidize meso-tetraphenylporphyrin 2a directly to the corresponding porpholactone 1a, [25a] but surprisingly, the direct oxidation pathway was most practical only for meso-tetrakis(pentafluorophenyl)porphyrin 2c. [25a,25d] However, the drawback of using porphyrin 2c is that the one-step reactions also readily generate higher oxidation products. Thus, method dependent, up to all Scheme 1. Stepwise syntheses of the bacteriodilactones 3 and their metal complexes 3M.