The synthesis, spectral and structural characterization of meso-aryl sapphyrins and rubyrins containing heteroatoms such as S, O, Se in addition to pyrrole nitrogens are reported. The synthesis of the desired expanded porphyrins has been achieved using a single precursor, the modified tripyrranes containing heteroatoms, through an unprecedented oxidative coupling reaction in moderately good yields. The product distribution and the isolated yields were found to be dependent on the nature of the acid catalyst and its concentration. Use of 0.1 equiv of acid exclusively gave 26π rubyrins while a higher concentration of acid gave a mixture of 18π porphyrin, 22π sapphyrin, and 26π rubyrin. Two additional products, 22π oxasmaragdyrin and 18π oxacorrole, were isolated in the reaction of oxatripyrrane. All of the sapphyrins and rubyrins exhibit well-defined intense Soret and Q-bands in the visible region, and the intensity and the position of the absorption maxima were dependent on the number and the nature of the heteroatoms present in the cavity. The solid-state structures of sapphyrins 8 and 9 show small deviations from planarity with formation of supramolecular ladders stabilized by weak C−H···S, C−H···Se, and C−H···N hydrogen bonds. 1H NMR studies reveal retainment of supramolecular arrays in solution. The TFA adduct of 8 shows unusual binding in which both the hydroxyl oxygen and the carbonyl oxygen participate, which is reminiscent of metal carboxylate binding and in total contrast to that observed for β-substituted sapphyrins. 1H NMR studies on rubyrins indicate rapid rotation of heterocyclic rings at room temperature, and protonation leads to a decrease in rate of rotation at room temperature. 1H NMR spectra of 10 and 17 in its free base form recorded at −50 °C reveal that the heterocyclic rings are inverted and protonation leads to dramatic ring flipping. However, 11 shows normal structure in the solution. The single-crystal X-ray structures of 10, 11, and 17 show that the heterocyclic rings, thiophene in 10, selenophene in 11, and furan and thiophene in 17, are inverted in the solid state.

Reductive coupling of dimethylfulvene with alkaline earth metals yields inseparable mixtures of the tetramethylethylene-bridged complex Me 4 C 2 (C 5 H 4 ) 2 M and the unbridged metallocene (i-PrCp) 2 M (M ) Mg, Ca, Sr, Ba). In contrast, the reductive coupling of phenylfulvene with activated calcium in THF gives nearly quantitative yields of a mixture of cis-and trans-diphenylethanediyl-bridged ansa-calcocenes. The more soluble cis isomer can be removed by recrystallization, yielding the C 2 -symmetric trans-Ph 2 C 2 H 2 (η 5 -C 5 H 4 ) 2 Ca-(THF) 2 (trans-2). The molecular structure of this ansa-calcocene shows the cyclopentadienyl rings to be bound in an η 5 fashion to the calcium center. This versatile reagent gives high yields of C 2 -symmetric transition metal ansa-metallocene complexes via the facile reaction of trans-2 with metal chlorides (e.g., FeCl 2 and ZrCl 4 ). The molecular structure of the corresponding ansa-zirconocene dichloride complex is described.

The reaction of methylphosphine sulfide, MeP(S)(3,5-Me2Pz)2, 1, with anhydrous CuCl2 affords a tetranuclear copper cluster[Cu2Cl2(3,5-Me2Pz)3(MePO3)]2, 2, and a dinuclear compound Cu2Cl4(3,5-Me2Pz)4, 3. This reaction involves a metal-assisted desulfurization along with concomitant hydrolysis of P-N bonds. The X-ray structures of 1-3 have been determined, and the crystal parameters for these are the following. 1: space group = C2/c, a = 15.2552(1) A, b = 8.7364(2) A, c = 21.4490(3) A, beta = 93.349(1) degrees, V = 2853.74(8) A3, and Z = 8. 2: space group = P2(1)/n, a = 12.5964(4) A, b = 15.7773(4) A, c = 13.9781(4) A, beta = 116.6280(10) degrees, V = 2483.32(12) A3, and Z = 2. 3: space group = P2(1)/c, a = 8.7137(8) A, b = 13.5493(14) A, c = 11.8847(12) A, beta = 106.179(2) degrees, V = 1347.6(2) A3, and Z = 2. The structure of 2 shows that it comprises two dinuclear copper cores bridged together by two tripodal methylphosphinate, MePO3, ligands. 2 is weakly antiferromagnetically coupled, as revealed by variable temperature magnetic susceptibility measurements.

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Reaction of PhP(O)(3,5-Me2Pz)2 or Ph2P(O)(3,5-Me2Pz) with PdCl2(C6H5CN)2 leads to a facile and complete P−N bond hydrolysis; in the former reaction a novel diphosphonic acid anion dimer has been isolated.

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Synthesis of 4-Fluororesorcinol and 4-Trifluoromethylresorcinol.-Less expensive, safer and easily scaled-up methods for the synthesis of 4-fluororesorcinol (IV) and 4-trifluoromethylresorcinol (VIII) are presented. Reaction of (I) with selectfluor T M reagent in a two-step procedure gives best results. Incorporation of a trifluoromethyl group into resorcinol derivative (V) is accomplished directly under Burton conditions via in situ generation and coupling of CF 3 Cu with the aryl iodide. -(YANG, J.-J.; SU, D.; VIJ, A.; HUBLER, T. L.; KIRCHMEIER, R. L.; SHREEVE, J. M.; Heteroat. Chem. 9 (1998) 2, 229-239; Dep. Chem., Univ. Idaho, Moscow, ID 83843, USA; EN)