271ChemInform Abstract Although the p-tolylcarbyne-W complex (I) does not itself react with alkynes, its protonation product, the title carbene, readily incorporates 1,2-diphenylacetylene (II) or 1,2-dimethylacetylene (IX) to give the vinylcarbene complex (III) and the η4-naphthol omplex (XI), respectively. The vinylcarbene complex (III) readily undergoes CO/I-substitution to yield the neutral vinylcarbene complex (V) (space group I2/a, Z = 8). With (BH4)-, (III) is converted into the allyl complex (VI). Treating (III) with the nitrone (VII) leads to the etallafuran complex (VIII) ( P21/n, Z=4) which possesses a planar metallafuran ring with bond distances in the ring implying delocalized bonding. The naphthol ligand from (XI) can be released by air oxidation. The naphthol ligand undergoes deprotonation to form the eutral allyl complex (XII). Reaction of the carbyne complex (XIII) with HBF4 in the presence of 1,2-dimethylacetylene (IX) under CO (X) leads to the formation of the diene complex (XIV) by benzannulation reaction from the carbyne, alkyne, and one CO ligand. The elevance of these various reactions to the general mechanism of naphthol formation from metal carbenes and alkynes is discussed.

TABLE IV: Dependence of **02 Phosphorescence Quantum Yields QP(X) on Solvent Xo solvent Xß ( ) C¡H¡ (4.7 ± 1.7) X 10"5 CH3CN (7.1 ± 2.8) X 10"5 CHClj (3.6 ± 1.4) X KT4 CS2 (4.0 ± 1.8) X 10"2 CC14 (9.0 ± 3.6) X 10"2 Freon 113(1.5 ± 0.6) X 10"' "Standard value ß ( ) determined by comparison of corrected fluorescence and phosphorescence spectra. The errors in ß ( ) are mainly determined by the uncertainty of gP(B).10 quantum yield (?P(Freon 113) = 0.15 ± 0.06 determined in this study agrees excellently with the value QP(Freon 113) = 0.15 ± 0.08 which was obtained from a comparison of the intensities of the spectrally unresolved emissions of TPP and O2 measured directly with a radiometer.10 The accordance of both results obtained by completely different techniques confirms impressively the accuracy of the quantum yield data of Table IV. DiscussionThe quantum yields of *02 formation by the sensitizers DCA, RUB, and TPP have been determined in six different solvents with rather high accuracy. Since ß ( ) values depend for DCA and RUB distinctly on solvent, probably for both sensitizers Sj-state and T,-state quenching by 02 produces *02. In contrast ß ( ) values for TPP depend only very weakly on solvent nature, indicating that essentially ,-state quenching by 02 leads to the formation of *02 by TPP.The *02 phosphorescence quantum yield gP(X) depends strongly on solvent nature and correlates exactly linear with ( ). Consequently the factors controlling *02 deactivation in solution determine also the solvent dependence of phosphorescence quantum yields. *02 deactivation by a solvent molecule occurs by a collisional energy-transfer process to a single oscillator of the accepting molecule. Accepting oscillators are terminal atom pairs of the solvent molecule like for example C-H or C-F. During this process electronic energy is converted mainly into vibrational energy. Since the deactivating power of an oscillator increases exponentially with the energy of the largest vibrational quantum, which can be accepted by the oscillator, solvents like CS2, CC14, and Freon 113 are distinguished by extremely long lifetimes and consequently by the largest phosphorescence quantum yields.2 The large '02 phosphorescence quantum yields found in this study are rather surprising, because from gas-phase absorption experiments it is known that *02 has an extremely long inherent lifetime of tp = 3850 s.23 However, already Long and Kearns demonstrated that the oscillator strength of the 02(3 8" -** 8) transition is by a factor of about 1000 larger in liquid solution than in the diluted gas phase.3 They explained the solvent-induced enhancement of the 02(3 8-*• ' 8) absorption qualitatively by a perturbation of the electronic states of 02 by the solvent X. In a collisional oxygen-solvent complex exchange mixing of higher excited complex states with the '('Ag'Xo) complex state should occur, finally introducing intensity from the allowed 'X0 -* *X, solvent transition into the 02(3 8~*Ag) transition. Although the solvent oxygen interaction is only o...

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