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Supplementary Material Available: Tables of atomic coordinates, isotropic thermal parameters, bond distances and angles, and X-ray crystallographic data for 9i (7 pages). Ordering information is given on any current masthead page.

Cupric chloride or bis( 1 -phenyl-l,3,5-hexanetrionato)dicopper(II) complex in the presence of triethylamine or copper(I1) species produced by reaction of cuprous chloride with oxygen in an aprotic solvent in the absence of added base all catalyze conversion of 3,5-di-tert-butylcatechol and 4-tert-butylcatechol with oxygen to the corresponding 1,2-benzoquinones. It appears that the catalytic sequence involves (a) formation of the dicopper(I1) catecholate intermediate, (b) electron transfer from the aromatic ring to two copper(I1) centers in the intermediate providing o-benzoquinone and two copper(1) centers, (c) irreversible reaction of the generated copper(1) species with oxygen to give the active copper(I1) reagent, and (d) reaction of this reagent with catechol leading to regeneration of the dicopper(I1) catecholate intermediate and formation of the water byproduct. Under anaerobic conditions the extent of the electron transfer from the substrate is determined by the thermodynamic stabilities of the copper(II)/copper(I) pairs. Copper(I1) species produced by oxidation of cuprous chloride in pyridine reacted with phenol to give a copper(I1) reagent which converted both o-benzoquinones and catechols under anaerobic as well as under aerobic conditions to monophenyl esters of muconic acid; the same reaction with phenol itself occurred only in the presence of oxygen. It was concluded that the latter reaction involves copper phenoxides as intermediates and subsequently demonstrated that this was indeed the case by using bona fide copper phenoxides. Using anhydrous ammonia as a nonhydroxylic nucleophile instead of alcohol or phenol nucleophiles in the reaction with copper-oxygen species resulting from the oxidation of cuprous chloride in pyridine provided a new copper(II)/ammonia reagent. This "CuO/NH," reagent reacts with o-benzoquinones and catechols under anaerobic and aerobic conditions to give muconic acid mononitriles, and with n-heptaldehyde, benzaldehyde, and cinnamaldehyde it provides the corresponding nitriles. Conversion of phenol to muconic acid mononitriles required oxygen. A different copper reagent, obtained by the addition of anhydrous ammonia to pyridine cupric methoxy chloride in pyridine, converts 4-tert-butylcatechol, 3,5-di-tert-butyl-1,2-benzoquinone, and 3-methoxy-4-tert-butylcatechol into the corresponding substituted muconic acid imides. Possible mechanisms for these transformations were discussed. and the conclusions about the role of oxygen were presented. Activation"; Hayaishi, O., Ed.; Academic Press: New York, 1974, Chapter 1 and references therein. Schoot-Viterkamp, A. J. M.; Mason, H. S. Proc. Natl. Acad. Sci. (I.S.A. 1973, 70, 993. Jolley, R. L.; Evans, L. H.; Makino, N.; Mason, H. S. J. Bioi. Chem. 1974, 249, 335. Makino, N.; McMahill, P.; Mason, H. S.; Moss, T. H. Ibid. 1974, 219, 6062. Ochiai, E. I. "Bioinorganic Chemistry"; Allyn and Bacon: Boston, 1977; Chapter 9, pp 218-262; Chapter 10, pp 263-278.(9) A common feature of multicopper enzymes is that they contain socalled type 3 co...

1153form-hexane, mp 214-217 "C (lit.I7 mp 217 "C from ethanol), was obtained in 47% yield: IR (Nujol) 1785 (vs), 1765 (m), 1745 (w), (C=O), 1650 (C=N); NMR (TFA) 6 4.06 (s, 3 H, OCH,), 7.23 (d, J = 10 Hz, 2 H), 6 H, vinyl H and CsH5), 8.33 (d, J = 10 Hz, 2 H).Oxidation of 1 with SeOZ. A mixture of 1.0 g (3.72 mmol) of 1 in 25 mL of acetic anhydride containing 1 drop of pyridine and 0.67 g (6 mmol) of SeOz was refluxed for 18.5 h. After cooling, the mixture was diluted with ether to precipitate selenium, which was filtered, and the filtrate was concentrated in vacuo. The residue was dissolved in ether (300 mL) and washed three times with H 2 0 and then with saturated NaHC03 solution (until the washes were basic). The ether solution was dried (Na2S04), filtered, and concentrated in vacuo, leaving a solid residue which was dissolved in hot isopropyl alcohol, yielding 0.51 g (55%) of 3, mp 163-166 "C.Oxidation of 2 with Phenylselenyl Chloride/HzOz. To a solution of 0.77 g (3.55 mmol) of 2 in 40 mL of ethyl acetate was added 0.77 g (4 mmol) of PhSeC1. The solution was stirred 8 h at room temperature followed by 6 h at reflux. Triethylamine (0.49 mL, 3.55 mmol) was added, and 30 min later TEAeHCl (0.31 g, 60%) was filtered. To the filtrate was added 0.7 mL (8.0 mmol) of 30% HzO2, and this solution stirred a t room temperature for 4 h. At the end of this time the solution was washed with two 25-mL portions of water and once with saturated Na2C03 solution. The organic layer was separated, dried (Na2S04), filtered, and concentrated in vacuo, leaving a yellow solid residue. Crystallization from isopropyl alcohol gave 157 mg (21%) of crystalline 3, mp 165-167 "C. Oxidation of 2 with t-BuOC1 in the Presence of KzCO3.A mixture of 0.62 g (2.48 mmol) of 2, 0.4 mL (3.36 mmol) of t-BuOC1, and 2.0 g (14.5 mmol) of finely divided anhydrous KzCO3 in 60 mL of CC1, was stirred at room temperature for 16 h and then refluxed 6.5 h. The reaction mixture was filtered and concentrated to dryness in vacuo, leaving a yellow solid residue. A yield of 0.4 g (66%) of 3, mp 161-164 "C, was obtained by crystallization from isopropyl alcohol.Although the title compounds seem t o be important ligands in the formation of cyclic coordinated complexes with transition metals, relatively little attention has been given to the preparation of o,w'-bis(tripheny1phosphine) polyethers from the corresponding dibromides.

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