Anthracene deuterated

Partial reduction of polyarenes has been reported. Use of boron trifluoride hydrate (BF3 OH2) as the acid in conjunction with triethylsilane causes the reduction of certain activated aromatic systems 217,262 Thus, treatment of anthracene with a 4-6 molar excess of BE3 OH2 and a 30% molar excess of triethylsilane gives 9,10-dihydroanthracene in 89% yield after 1 hour at room temperature (Eq. 120). Naphthacene gives the analogously reduced product in 88% yield under the same conditions. These conditions also result in the formation of tetralin from 1-hydroxynaphthalene (52%, 4 hours), 2-hydroxy naphthalene (37%, 7 hours), 1-methoxynaphthalene (37%, 10 hours), 2-methoxynaphthalene (26%, 10 hours), and 1-naphthalenethiol (13%, 6 hours). Naphthalene, phenanthrene, 1-methylnaphthalene, 2-naphthalenethiol, phenol, anisole, toluene, and benzene all resist reduction under these conditions.217 Use of deuterated triethylsilane to reduce 1-methoxynaphthalene gives tetralin-l,l,3-yielding information on the mechanism of these reductions.262 2-Mercaptonaphthalenes are reduced to 2,3,4,5-tetrahydronaphthalenes in poor to modest yields.217 263... 

Fig. 27. Semilogarithmic plot of the nonradiative triplet rate constant against (E— o)/> for the normal and deuterated hydrocarbons listed in Ref. t)). The broken line, derived from phosphorescence spectra, is taken from Ref. t). The slopes of the two solid lines differ by a factor 1.35. (O.Ci-jjH, E = 4000 cm l 0 Ci fl Z>u, =5500 cm t). The following totally deuterated hydrocarbons are included benzene, triphenylene, acenaphtene, naphthalene, phenanthrene, chrysene, biphenyl, p-terphenyl, pyrene, 1,2-benzanthracene, anthracene (in the order of increasing /S). (From Siebrand and Williams, Ref. l)...

It is clear that deuterium as a substituent has the electron-donating effect. In other words, it can decrease electron affinity of the whole molecule. Potentials of reversible one-electron reduction for naphthalene, anthracene, pyrene, perylene, and their perdeuteriated counterparts indicate that the counterparts exhibit slightly more negative potentials (Goodnow and Kaifer 1990, Morris and Smith 1991). For example, the measurable differences in the reduction potentials are equal to -13 mV for the pair of naphthalene-naphthalene-dj or -12 mV for the pair of anthracene-anthracene-djo. The possible experimental error does not exceed 2 mV (Morris and Smith 1991). In another example, in DMF with 0.1 M n-Bu4NPFg, the deuterated pyrenes were invariably found to be more difficult to reduce than pyrene itself. The largest difference observed, 12.4 mV, was between perdeuteriated pyrene and pyrene bearing no deuterium at all with standard deviations between 0.2 and 0.4 mV (Hammerich et al. 1996). 

The regiochemistry of deuteration of polycyclic carbonyl compounds such as methyl derivatives of benz[de]anthracen-6- and -7-one is subject to orbital control.147 Charge alternation and deuterium isotope effects in these and related compounds were studied by NMR and MNDO methods. 

PhCD3 + C14H10 - PhCD2H, PhCDH2, PhCH3 + deuterated anthracenes,... 

Figure 4 Example of the application of chrom-NMR/HRMAS with regular NMR solvents and bare silica as a solid phase. Left panel aromatic molecule homologues in deuterated chloroform benzene, naphthalene and anthracene. Right panel alcohol mixture ethylene glycol, phenol, isopropanol in deuterated water. Adapted with permission from Ref. 53. Copyright 2008 Elsevier.

Figure 2.1. Dispersion of phonons in a deuterated anthracene crystal (S. L. Chaplot et al., 1982). Upper part calculated spectra. Lower part dispersion measured by neutron scattering. The Raman-active modes at k = 0(F) are marked R, and have symmetry /4,(S) or Bt(A). Note the weak dispersion of the lower R mode along c. ... 

As regards the profile of the potential energy surface, the behavior of deuterated vinyl anthracene (] ) provided valuable informations (26), On benzil sensitized irradiation, its E-isomer... 

Subsequent to the anthracene studies, picosecond-beam measurements of IVR in a number of other molecules have been made. These molecules include deuterated anthracenes,44 t-stilbene,45 and some alkyl anilines.46 One of the most significant results of these studies is that they have indicated that vibrational coherence30,40 (phase-shifted quantum beats) is a general phenomenon in molecules. Thus, it appears that an accurate understanding of IVR must rest firmly on an accurate understanding of vibrational coherence. 

Picosecond-beam studies44 of IVR in deuterated anthracenes have also been performed. The main impetus for performing such experiments was to assess the generality of the anthracene results and to determine the effects that changes in molecular symmetry and vibrational density of states have on IVR. We discuss results pertaining to these studies after the anthracene subsection. 

As of this writing, our picosecond-beam results44 on vibrational coherence in deuterated anthracenes have yet to be published. The treatment of these results here will be very brief. 

Polycyclic Aromatics. Extensive replacement of hydrogen by lithium in polycyclic aromatic hydrocarbons has been demonstrated by Halasa (15). Anthracene, biphenyl, fluorene, indene, and ferrocene (16) undergo polymetalation by n-butyllithium—TMEDA in hexane at 70°C for 24 hours. The products are insoluble mixtures of polylithio compounds containing up to 10 lithium atoms per molecule. Derivatization was accomplished using both D20 and trimethylchlorosilane and by analyzing the mixture of deuterated or silylated products by mass spectrometry. The results for anthracene, which are typical, appear in Table I. 

The water or soil samples are spiked with appropriate amounts of deuterated surrogate standard compounds (orf/zo-terphenyl, a mixture of djo-acenaphthene, djo-phenanthrene, di2-benz (a) anthracene, and di2-perylene) prior to extraction. Water samples are extracted according to the EPA Method 3510 Separator Funnel Liquid-Liquid Extraction. 

A small decrease in < >, (from 0.27 to 0.24) was observed upon deuteration of anthracene. 

In the early 1950s reports appeared of the Co2(CO)8-catalyzed hydrogenation of polycyclic aromatic hydrocarbons in the presence of synthesis gas (CO/H2). In 1975 Halpem proposed that these reactions occurred by sequential H transfer from a cobalt hydride formed in situ (Scheme 1.7) [47]. This transfer must be reversible, because treatment of anthracene with (CO)4CoD leads to deuterated anthracene [48]. (Syn addition of Co-D would not lead to H/D exchange.)... 

An IR spectrum has been recorded for the tetrabromoaluminate (vdth an admixture of heptabromodialuminate) of a 10-H-anthracenium ion in the range of90-3100 cm Based on the results of deuteration at 9- and 10-positions and of comparison with the spectra of anthracene, 9- and 10-substituted anthracenes and of an acridi-nium cation, the authors have performed the assignment of the observed absorption bands of the anthracenium ion and of the anions AlBr and Al Brf. The stretching... 

Cycloadditions. The dienophilic properties of ( )-phenyl-sulfonyl-2-trimethylsilylethylene allow the preparation of adducts with reactive dienes such as cyclopentadiene and anthracene. The adducts are smoothly converted to alkenes upon treatment with fluoride ion, establishing the equivalence of the title reagent to acetylene. Alkylation of the a-sulfonyl carbanion can precede the elimination such that synthetic equivalents to HC CH, HC CD, and RC CH are available. The use of this reagent is highlighted by the synthesis of several functionalized dibenzobarrelenes (eq 1). The equivalency to DC CD and RC=CD is illustrated by the preparation of deuterated derivatives. 

Highly reactive calcium can be readily prepared by the reduction of calcium halides in tetrahydrofuran (THF) solution with preformed lithium biphenylide under an argon atmosphere at room temperature [2]. This colored calcium species seems to be reasonably soluble in THF. However, the reactive calcium complex prepared from preformed lithium naphthalenide was insoluble in THF solution and precipitated out of solution to give a highly reactive black solid. As this lithium naphthalenide generated calcium species was insoluble in most deuterated solvents and reacted with deuterated DMSO and DMF, the exact nature of this black calcium complex has not been determined. Acid hydrolysis of the black material releases naphthalene as well as THF. Accordingly, the most likely structure of the black material is a Ca-naphtha-lene-THF complex similar in nature to the soluble magnesium-anthracene complex reported [3]. 

Other organic compounds that can be used as internal standards are as follows 2,4,5,6-tetrachloro-m-xylene [150], octachloronaphthalene [135], PCNB [54], 1,2,3,4-tetra-chloronaphthalene [135], 2,6-dichlorobenzonitrile [84], deuterated naphthalene [141], deuterated benzo(a)anthracene [141], l,4-dichlorobenzene-d4 [151], naphthalene-dg [151], acenaphthene-dio [151], phenanthrene-dio [151], chrysene-di2 [151] and perylene-di2, [151], and 13C-1,2,3,4-TCDD [128]. 

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