1,2-Acenaphthenequinone

There is a rich Hterature of nonben2enoid quinones such as acenaphthenequinone [82-86-0] (1,2-acenaphthylenedione) (19) (14,15). More recendy... 

Acenaphtheno[l,2-e][l,2,4]triazolo[4,3-h][l,2,4]triazine 747 was prepared (79AP147) by cyclizing 3-hydrazinoacenaphtheno[l,2-e][l,2,4]tria-zine 746 with formic acid. Reaction of 746 with sugars gave the hydrazones, which cyclized with iron(III) chloride to give 748 (93BCJ00). Similarly, the acetaldehyde derivative of 746 was cyclized to 748. The structure of 748 (R = Me) rather than 747 (R = Me) was deduced by unequivocal synthesis of the latter by condensation of acenaphthenequinone with 3,4-diamino[l,2,4]triazole (Scheme 155). 

Scheme 1. Synthesis of Catalysts (i) HCl (ii) Acenaphthenequinone, MeOH (iii) (DME)NiBr2, CHjCb,...

The bidentate ligands were prepared by the Schiff-base condensation of two equivalents of the desired 2,6-dialkyl substituted anilines with acenaphthenequinone as in the scheme 1, The pre-catalysts, formed by addition of the ligand to (DME)NiBr2 are isolated and purified. The products were characterized by h, C NMR, GPC, DSC and Elemental Analysis. 

General procedures for the synthesis of ligands and metal complexes are shown in Scheme 1. For file synthesis of 2a acenaphthenequinone (0.38 g, 2.1 mmol) and a,a-bis(4-amino-3,5-dimethylphenyl)-toluene(Kccess) were dissolved in 50 mL of CH3OH in a round-bottom flask. Five drops of formic acid were added, and the sealed solution was stirred at 50 C overnight. After filtration, the red solid was washed with hot methanol and dried to give 1.2 g of red powder in 50 % yield. 

Acenaphthenequinone has been prepared from acenaplithene by oxidation with chromic acid, 1 2 3 with calcium permanganate,4 with air in the presence of catalysts in various solvents,6 6 7 and by the formation of an oxime with amyl nitrite followed by hydrolysis.8... 

Diamino-4(3/f)pyrimidinones on reaction with a-diketones give (84JHC1537 85JHC1317) pyrimido[l,2- ][l,2,4]triazines 240. Similarly, the condensation of 2,3-diamino-4(3i/)pyrimidinones with cyclohexandi-one, 1,2-naphthoquinone, acenaphthenequinone, and phenanthraquinone gives the respective condensed pyrimidotriazines of general structure 241 (85JHC1317). 

The reaction sequence outlined in Scheme 20.30 for the preparation of the chlorinated enyne-allenes was successfully adopted for the synthesis of the C44H26 hydrocarbon 251 having a carbon framework represented on the surface of C60 (Scheme 20.50) [83]. Condensation of the monoketal of acenaphthenequinone (243) with the lithium acetylide 101 afforded the propargylic alcohol 244. On exposure to thionyl chloride, 244 underwent a cascade sequence of reactions as described in Scheme 20.30 to furnish the chloride 248. Reduction followed by deprotection produced 250 to allow a repeat of condensation followed by the cascade transformation and reduction leading to 251. 

The bismuth ylides, Ph3Bi=CHCOR, do not react with simple ketones and electron-rich olefins probably because of their relatively low electrophilic character. However, Ph3Bi=CHCOR reacts with a-keto esters [46, 67, 68], benzils [46, 67-69], orf/to-quinones [46, 67, 68], and acenaphthenequinone [70] to give epoxides, (9-arovl enolates, 3-hydroxytropones, and 3-hydroxyphenalenones, respectively, accompanied by the formation of Ph3Bi (Scheme 11). In particular, transposition and ring expansion reactions are of interest from a mechanistic point of view, since these reaction modes are unprecedented in ylide chemistry. 

A convenient route to pyridazine derivatives is found in the reaction of monohydrazones of 1,2-diketones with DMAD. The reaction of benzil monohydrazone with DMAD, for example, gives a mixture of products consisting of dimethyl 5,6-diphenylpyridazine-3,4-dicarboxylate (135), benzil dimethyl oxaloacetate ketazine (136) and benzil bisketazine (137). A similar reaction of acenaphthenequinone... 

Condensation of 4,5-diaminoacenaphthene with cyclic a-diketones (acenaphthenequinone, phenanthrenequinone) gives rise to b-side anne-lated acenaphtho [4,5- >/]-l,4-diazepine derivatives 523 (IICB2852 ... 

Diketones are easily reduced electrochemically because of the mutual electron-withdrawing effect of one carbonyl group on the other. Two-electron reduction usually takes place to afford an enediolate (62), which can then react with an electrophile E present in the medium (equation 31 see also Schemes 10 and 13) an alpha-hydroxy ketone is formed by subsequent tautomerization when E = H1,85,86. An unusual exception to the generalization that these substances undergo two-electron reduction is the electrochemical behavior of acenaphthenequinone (63), which is converted to the expected enediol dibenzoate (64) in the presence of aroyl chlorides but affords the dimeric substance 65 (shown to be the meso diastereomer by X-ray crystallography) in the presence of acetic... 

Dication 79 has been observed by low temperature NMR from FSC>3H-SbF5 solutions.34 Although diprotonated quinones (83-84) are expected to have extensive delocalization of the positive charges, several have been reported, and their condensation chemistry suggests a relatively high level of electrophilic reactivity (eq 19).37 Diprotonated acenaphthenequinone and aceanthrenequinone (83 and 84) have been... 

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