Indeno

BghiP = benzo(g,h,i)perylene CHy = chrysene Per = perylene BbF = benzo-(b)fluoranthene BkF = benzo-(k)fluoranthene BaP = benzo-(a)pyrene IP = indeno-(l,2,3-cd)pyrene Att = anthanthrene. 

Fig. 42 Chromatogram of polycyclic aromatic hydrocarbons on caffeine-impregnated precoated silica gel 60 HPTLC plates with concentrating zone (Merck). The following can be recognized in increasing Rf value. — 1. benzo(ghi)perylene, 2. indeno(l,2,3-cd)pyrene, 3 benzo(a)pyrene, 4. benzo(b)fluoranthene, 5. benzo(k)fluoranthene, 6. fluoranthene.

Chemical Name 2,3,4,9-tetrahydro-2-methyl-9-phenyl-1 H-indeno[2,1, c] pyridine tartrate Common Name 2-methyl-9-phenyl-2,3,4,9-tetrahydro-Tpyridindene tartrate Structural Formula CcH, ... 

One of the first reactions to be carried out in a molten salt (albeit at 270 °C) was the Scholl reaction. This involves the inter- or intramolecular coupling of two aromatic rings. A example of this reaction, in which 1-phenylpyrene was cyclized to indeno[l,2,3-cd]pyrene [26] is given in Scheme 5.1-7. A more elaborate version of the Scholl reaction is shown in Scheme 5.1-8 and involves bicyclization of an aromatic cumulene [27]. 

Four tautomeric forms I -4 can be drawn for azacycloheptatriene and of these four tautomers only 1 ff-azepine ( ) is formally a fully conjugated system however, the chemistry of all four tautomers is covered in this section together with the three isomeric, fully conjugated, cyclopentazepines 5-7, in which nitrogen is located in the seven-membered ring, and their indeno analogs. 

Unsubstituted indenoazepines are unknown however, derivatives of indeno[l,2-7>]azepine, e.g. 17,56 and indeno[l,2-<7]azepine, e.g. 18,57 have been reported. 

Indeno[l,2-rf]azepin-4-ol and its 10-bromo derivative appear to be in the lactam form 20. In base solution, however, there is UV and HNMR spectroscopic evidence for the 14k fully conjugated anions, e.g. 21.57... 

The thermal decomposition of ethyl diazoacetate in 9//-indcno[2,l -6]pyridine (3) effects expansion of the pyridine ring to give ethyl indeno[l,2-Z>]azepine-3-carboxylate (4), the first example of the indeno[l,2-Z>]azepine system.56... 

Methylation of indeno[l,2-r/]azepin-4(3//)-one (22) with iodomethane under phase transfer conditions produces the A-methyl derivative, whereas ethylation with Meerwein s reagent yields purple crystals of the indeno[l, 2-r/Jazepine 23, a 147r-aromatic system.57 1 l-Bromo-4-ethoxyin-deno[l,2-r/]azepine (69% mp 143-144°C) can be prepared similarly. 

Base-catalyzed condensation of 2-iminoindane-2-carbonitrile (62) with phthalaldehyde affords indeno[2,l-c]-2-benzazepine-5-carbonitrile (63) in excellent yield (95%),97 which is identical to an uncharacterizcd byproduct obtained earlier98 by condensing benzene-1,2-diacetonitrile with phthalaldehyde in the presence of sodium methoxide. The naphthalene analog 64 is prepared by condensing naphthalene-2,3-dicarbaldehyde with the indanecarbonitrile 62 under similar conditions. 

The pyrazolotrithiadiazepines 3 are stable colorless crystalline solids. They decompose at 210 C with loss of nitrogen and HNS to yield deeply colored rearranged indeno-1,2,3-dithiazoles, e.g. decomposition of 3b.392... 

Dihydro-1-vinylnaphthalene (67) as well as 3,4-dihydro-2-vinylnaphtha-lene (68) are more reactive than the corresponding aromatic dienes. Therefore they may also undergo cycloaddition reactions with low reactive dienophiles, thus showing a wider range of applications in organic synthesis. The cycloadditions of dienes 67 and 68 and of the 6-methoxy-2,4-dihydro-1-vinylnaphthalene 69 have been used extensively in the synthesis of steroids, heterocyclic compounds and polycyclic aromatic compounds. Some of the reactions of dienes 67-69 are summarized in Schemes 2.24, 2.25 and 2.26. In order to synthesize indeno[c]phenanthrenones, the cycloaddition of diene 67 with 3-bromoindan-l-one, which is a precursor of inden-l-one, was studied. Bromoindanone was prepared by treating commercially available indanone with NBS [64]. 

Imidazole derivatives 380 Imperatorin 65 Impregnation of TLC layers 86 -with caffeine 86 -with silver nitrate 86 -with tungstate 86 Indeno(l,2,3-cd)pyrene 39,85 Indicators, pH- 303 -, reagents 45 Indium cations 144 Indoleacetic acid 45... 

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