Biphenylenes. Part XVI. Preparation and Baeyer–Villiger oxidation of some 2-acetylbiphenylenes

Blatchly, J. M.; Gardner, D. V.; McOmie, J. F. W.

doi:10.1039/j39670000272

Cited by 6 publications

(7 citation statements)

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“…The above mentioned studies on the exchange of BPH with trifluoroacetic acid (12, 13) do not provide information on the amount of decomposition, a factor which is important in preparation of the fully deuterated compound in reasonable yield. On the other hand the reported kinetic data (12), despite referring to a somewhat different exchange (17), satisfactorily account for the deuterium percentage obtained in run 4 (Table I); the same experiment also shows that the decomposition rate prevails for exchange in the a-position. In an attempt to find a better exchange medium, D2SO4 (18) or D3PO4 (19) was added to CF3COOD, thus increasing the value of the acidity function (20) (and hence the exchange rate in the a-position (21)) of the exchange agent, which still remains a sufficiently good solvent for BPH.…”

supporting

confidence: 51%

“…Kinetic data for hydrogen isotopic exchange in trifluoroacetic acid and trifluoroacetic acid -70 % HC104 are also available (12,13) and the /?-position has been shown to be more reactive than the a one, which has almost the same reactivity as the /?-position in naphthalene (13). Since each of the hydrogen atoms of naphthalene exchange with 50% D2SO4 (14), the first exchange experiments attempted were wit11 30-70 % D2SO4 (runs 1-3, Table I).…”

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confidence: 99%

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Hydrogen isotopic exchange in biphenylene and the preparation of biphenylene-d₈

Lunelli¹,

Pecile²

1968

Can. J. Chem.

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The hydrogen isotopic exchange with basic and acidic agents has been widely investigated with the aim of preparing fully deuterated biphenylene. It has been noted that the very strong base KOD completely decomposes the hydrocarbon, while the strong base NaOD leads to random exchange, and the medium strength base Ca(OD)2 gives preferential exchange in a-position. Since the stability of biphenylene is less in acid mixtures than in basic ones, only acids of medium strength, which give preferential exchange in P-position, can be used.Good results in preparing fully deuterated biphenylene are obtained from two methods. The first of these consists of two exchanges which occur successively; one with an acid mixture and the other with a base. Both agents are of medium strength. The second method entails repeated exchanges with the strong base NaOD supported on Ca(OD)2. The latter method gives the highest isotopic purity and the best yield, as well as being much easier to carry out.Canadian Journal of Chemistry, 46, 391 (1968) The study of the vibrational spectrum of biphenylene (BPH), which is in progress in this laboratory,2 has required the availability of the corresponding fully deuterated compound (BPH-d8). Since the reported syntheses of BPH, which give reasonable yields (1-3), did not appear to be conveniently adaptable3 to the preparation of BPH-ds, the hydrogen isotopic exchange method was chosen, since it gives good results with aromatic compounds (5,6).The reactivity of the hydrogen atoms of BPH has been the object of both theoretical and experimental research (7-1 1). Kinetic data for hydrogen isotopic exchange in trifluoroacetic acid and trifluoroacetic acid -70 % HC104 are also available (12,13) and the /?-position has been shown to be more reactive than the a one, which has almost the same reactivity as the /?-position in naphthalene (13). Since each of the hydrogen atoms of naphthalene exchange with 50% D2SO4 (14), the first exchange experiments attempted were wit11 30-70 % D2SO4 (runs 1-3, Table I). In these reaction mixtures, the D / H atom ratio was 10:l and therefore BPH with 90% deuterium content could be expected if a random distribution of hydrogen isotopes were obtained. The results (Table I) show that an increase of acid concentration results in an lThis investigation was supported by the National Research Council of Italy, Chemistry Committee.2C. Pecile and B. Lunelli. J. Chem. Phys. In preparation.3A new method, which may be adaptable, was reported briefly (4) when the present work was in an advanced stage.increase in deuterium content of the product but a poorer yield of recovered BPH is obtained. The 60% D2SO4 gives an acceptable yield but the percentage of deuterium is too far below 90 %; the 70 % D2SO4 (5 h at 110 "C) produces nearly complete decomposition.Results obtained with other acids were not useful. Gaseous DCl(15) bubbled through a 5 % solution of BPH in benzene or in carbon disulfide in the presence of AlC13 gave unexchanged BPH and 30 % decomposition products. Liquid anhydrous ...

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supporting

confidence: 51%

mentioning

confidence: 99%

Hydrogen isotopic exchange in biphenylene and the preparation of biphenylene-d₈

Lunelli¹,

Pecile²

1968

Can. J. Chem.

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“…We anticipated reaction at the 2-position of biphenylene since it is the most reactive towards electrophilic substitution, [17] and this was confirmed by the single-crystal X-ray structure of the orange crystals of the mono-substitution product, two views of which are shown in Figure 3. The structure of C 60 F 17 (1-naphthyl) ( Figure 5) was confirmed by EI mass, 1 H, and 19 F NMR spectra (see Experimental Section).…”

Section: Substitutions Of the Individual Aromatic Compoundsmentioning

confidence: 76%

“…The latter shows the main fragmentation ion at 1043 amu (C 60 F 17 + , due to loss of the aryl group) and 828 amu (C 60 anisyl + , due to loss of all of the fluorine atoms).…”

Section: Spectroscopic Datamentioning

confidence: 98%

Electrophilic Aromatic Substitution by the Fluorofullerene C₆₀F₁₈

Darwish

Avent

Abdul‐Sada

et al. 2004

Chemistry A European J

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The FeCl3-catalysed arylation of C60F18 gives tri-substituted compounds C60F15Ar3, where Ar=phenyl, 4-tolyl, 4-methoxyphenyl, 4-phenoxyphenyl, 4-chlorophenyl, 3,4-dichlorophenyl, 2-biphylenyl and 2-fluorenyl, together with some bis- and mono-substituted product. Bis-substitution was achieved with biphenylene and fluoranthene, and mono-substitution with biphenylene (2-position), pyrene (1-position), and naphthalene (1- and 2-positions); the tris-phenyl and tris-biphenylene derivatives are fluorescent. The 2-naphthyl substituent freely rotates at 328 K, whereas rotation of the 1-naphthyl substituent is prevented by interaction of the peri-hydrogen atom with fluorine. The 1-naphthyl derivative eliminates a molecule of HF during EI mass spectrometry, whilst the 2-naphthyl derivative eliminates HF and all fluorenes to give a naphthaleno[60]fullerene. The reaction rate is relatively unaffected by electron supply in the aryl rings, but no product was obtained with benzotrifluoride which defines the lower reactivity limit. The low discrimination between aromatics makes it possible to isolate derivatives having different aryl groups attached to the cage. Reactions occur mainly when the reagent solutions (or solutions in 1,2-dichlorobenzene) are evaporated to dryness. In most FeCl3-catalysed reactions, unreacted C60F18 was recovered, more if the less effective SnCl4 was used as a catalyst; use of AlCl3 resulted in polyarylation and degradation of the C60F18. The structure of C60F17(1-biphenylyl) was confirmed by single-crystal X-ray analysis. Reaction of C60F18 with perylene/FeCl3/o-dichlorobenzene gave red fluorescent "tagliatelli"-like threads (up to 1 cm long) of self-assembled pi-stacked tetrachloroperylene arising from chlorination by FeCl3.

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“…(iv) o+-Values may be derived as follows (positions in parentheses) : -0.40(1) -0.385(2) -0.34(3) -0.435(4), -0.49(5), -0.44(6), and -0.46 (7). Since the reactivities of all the positions are rather similar it follows that in reactions of low selectivity, substitution will produce fairly equal amounts of all isomers.…”

Section: Results Andmentioning

confidence: 99%