Anthracene hydride

Anthracene hydride (the anion derived from 9,10-dihydroanthracene) reacts rapidly with chalcone to form an anionic Michael adduct along with a chalcone dimerization product (Scheme 83). Prolonged reaction in the presence of anthracene hydride cleaves the Michael adduct into anthracene and the enol-ate of the saturated ketone. The partial structure RCCCO is essential for this fragmentation, as mesityl oxide, for example, gave only the Michael adduct. 

Hydrogen and sodium do not react at room temperature, but at 200—350°C sodium hydride is formed (24,25). The reaction with bulk sodium is slow because of the limited surface available for reaction, but dispersions in hydrocarbons and high surface sodium react more rapidly (7). For the latter, reaction is further accelerated by surface-active agents such as sodium anthracene-9-carboxylate and sodium phenanthrene-9-carboxylate (26—28). 

An interesting reaction of dimsyl anion 88 is the methylation of polyaromatic compounds. Thus naphthalene, anthracene, phenanthrene, acridine, quinoline, isoquinoline and phenanthridine were regiospecifically methylated upon treatment with potassium t-butoxide and DMSO in digyme or with sodium hydride in DMSO123-125. Since ca. 50% of D was found to remain in the monomethyl derivative 93 derived from 9-deuteriophenanthrene 92, the mechanistic route shown in Scheme 2 was suggested125. 

The same nonpolar conformation can be achieved by conversion to bicyclic structures. 1,4-Cyclo-addition of ethylene to anthracene-9-carboxylic acid gives acid 68. Successive conversion to the N-methylamide, via the acid chloride, followed by reduction with lithium aluminum hydride produced... 

The finely divided hydride produced by pyrolysis is pyrophoric in air, while synthesis from the elements produces a substantially air-stable product [1]. That prepared by reduction of butylmagnesium bromide with lithium tetrahydroalumi-nate is pyrophoric and reacts violently with water and other protic compounds [2], The hydride produced from magnesium anthracene has a very large specific surface area and is pyrophoric [3], In the context of use of the hydride for energy storage purposes, ignition and combustion behaviour of 100-400 g portions were studied, as well as the reaction with water [4],... 

Hydride transfer from alkenes was also proposed to occur during sulfuric acid-catalyzed alkylation modified with anthracene (77). Then the butene loses a hydride and forms a cyclic carbocation intermediate, yielding—on reaction with isobutene—trimethylpentyl cations. This conclusion was drawn from the observation of a sharp decrease in 2,2,3-TMP selectivity upon addition of anthracene to the acid. 

Catalysts and reaction conditions used are generally similar to those used for olefin isomerization. Catalysts reported are sodium-organosodium catalysts prepared in situ by reaction of a promoter such as o-chloro-toluene or anthracene with sodium 19-24), alkali metal hydrides 20,21), alkali metals 22), benzylsodium 26), and potassium-graphite 26). These catalysts are strong bases that can react with alkylaromatics to replace a benzylic hydrogen [Reaction (2)]. 

Acenaphthylene heated with lithium aluminum hydride in carbitol at 120° gave 97% yield of acenaphthene [403], Anthracene is reduced very easily to the 9,10-dihydro compound by catalytic hydrogenation [78] and by sodium... 

In contrast to the adducts of many dienes with maleic anhydride, the above adducts are characteristically stable to heat some do not dissociate at temperatures as high as 300°. This property is apparently associated with the sulfone group, since reduction of the anthracene adduct (346) with lithium aluminum hydride affords the corresponding cyclic sulfide, which readily dissociates at 250° to give anthracene and benzo[6]thiophene.726... 

The cis- 1,2-glycols, obtainable from the parent aromatic hydrocarbon by osmium tetroxide hydroxylation, can be converted to the corresponding trans-1,2-glycols by oxidation-reduction, using a mixture of dimethyl sulfoxide, sulfur trioxide, and pyridine, followed by lithium aluminum hydride reduction. The trans- 1,2-glycols can be dehydrated to arene oxides using DMF-DMA as mentioned above. Benzo[a]pyrene 4,5-oxide (28) and 7,12-dimethylbenz[a]anthracene 5,6-oxide (30) have been prepared by this method in 68 and 80% yields, respectively.18... 

An unsaturated compound in the course of its isomerization in magnesium-containing films performs two functions (i) it forms a catalyst when the Mg4 cluster is inserted into the activated C-H bond, and (ii) it acts as a reaction substrate. The stages of the synthesis of the catalyst and isomerization can be separated. For example, anthracenyltetramagnesium hydride can be preliminarily obtained in anthracene-magnesium films, and then it can be used as a catalyst. The introduction of this cluster compound into a solution of allylbenzene or methylindene at room temperature ensures high yields of multiple bond migration products. 

Cp ZrCl3] reacts with [Mg(anthracene)(THF)3] to yield the [r 4-anthracene)Cp ZrCl2] anion complex 54 (with [Mg2(p-C1)3(THF)6]+ countercation).56 Treatment of [CpZrCl(dmpe)2] with butadiene yields [CpZrCl(,s-cz, s-r 4-butadiene)(dmpe)] (55).57 Subsequent reaction of such systems (M = Zr, Hf) with hydride ( Red-Al ) leads to [CpM(H) (butadiene)(dmpe)] (56), which rapidly insert terminal alkenes to give the corresponding [CpM(-CI 12C I I2R)(.s-cu-r 4-bmadiene)(dmpe)] systems58 (Scheme 18). 

Treatment of an ethereal solution of 4-oxo-dihydro-l,3-diaza-anthracene (108) with lithium aluminum hydride reportedly resulted in the reduction of only the 1,2-carbon-nitrogen double bond with 4-oxo-l,2,3,4-tetrahydro-l,3-diazaanthracene (109) being the only product isolated.134 Apparently conditions were not sufficiently vigorous for the further reduction of the tautomeric form of 109, or possibly the formation of a complex with the aluminohydride pre-... 

Virk and Garry (24a) have recently investigated hydrogen transfer from cyclohexanol to anthracene and phenanthrene and have reported well-behaved second-order kinetics. These workers suggest that this reaction may occur by a concerted molecular H2-transfer. Simple second-order kinetic behavior, however, is also consistent with molecular disproportionation (and also with hydride, H, transfer). However, if it is assumed that (k, /k ) = 0.1, predicted rates are only 1/100... 

Materials. Rectified DOL was dried over calcium hydride and distilled from a stock solution of colored sodium anthracene in a vacuum system. BCMO, St, and ethylene dichloride were purified by the usual procedure and dried with calcium hydride and barium oxide. Et3OBF4 was prepared in a high vacuum system (10 6 mm. Hg). 

Catalytically prepared magnesium hydride has been used as an alternative to magnesium anthracene [10]. 

Radical cations have also been trapped with the hydride ion. Irradiation of aromatic hydrocarbons such as phenanthrene, anthracene and naphthalene in aqueous acetonitrile containing sodium borohydride and an electron acceptor produces the dihydroarenes (Yasuda et ai, 1981b). With monoalkyl naphthalenes reduction in both the unsubstituted and substituted rings occurs... 

---