Indeno thiophene

Maier EA, Schimmel H, Hinschberger J, Griepink B, and Jacob J (1994) The certification of the contents (mass fraction) of pyrene, benz[a]anthracene, benzo[o]pyrene, benzo[e]pyrene, benzojb]-fluoranthene, benzo[fe]fluoranthene, indeno[i,2,3-cd]pyrene and benzo[b]naphtho[2,i-d]thiophene in dried sewage sludge. BCR Information, Reference Materials. Report EUR 15039 EN, 51 pp. 

Decarboxylation of 5,7-dimethyl-8-oxo-6-aza-8//-indeno[2,1 - ]thiophene-4-carboxylic acid could be effected by heating an admixture of it and copper powder <87H(26)1535). Direct sublimation in vacuo afforded the desired product (58%). 9-Chloro-2- and 3-methyltriazolo[4,5-/]quinoline-7-carboxylic acids are decarboxylated under similar conditions <93H(36)259>. The cyano group of 8-cyano-7-oxo-4,5,6,7-tetrahydrothiazolo[4,5-/]quinolines can be converted into an amino group by cone. HC1 mediated hydrolysis to the amide, followed by Hofmann rearrangement <89H(29)I517>. 

Cyclization of a 4-(3-thienyl)-3,5-pyridinedicarboxylic acids in hot H2S04 was shown to be a viable route to the substituted 8-oxo-6-aza-8//-indeno[2,1-6] thiophenes (e.g. (28)) (Equation (8)) <87H(26)1535>. In the case of the dimethylated carboxylic acid shown, the neutral tricyclic heterocycle (28) is obtained in 21% yield. 

Methoxycarbonyl-4H-(,thieno[3,2-c]-pyrazolo[3,4-a -naphtfwlin) (Schmp. 252-2551) wird durch Cycloaddition von Propinsaure-methylester mit 4-Diazo-4H-(indeno[l,2-c]thiophen> (14%) oder durch Hydrolyse von 4,4-Dimethoxycarh[Pg.812]

Hetero-/-fused derivatives of indeno[/i]benzopyrans result from the chromenylation of fluoreno[3,4-()][l]benzofuranols and related S andNMe analogues. The furo- 25 and thieno-26 [2,3-7]benzopyrans show absorption bands between 450 - 530 nm and 550 - 640 nm according to the substituents on the gem diaryl function and generally appear as various shades of brown. The half-lives vary between 1 and 6 minutes, with the thiophene analogues exhibiting faster fade rates than the furan derivatives. The closed form of the sole pyrano-... 

The indeno[l,2-Z)]thiophene 27 was converted to 2-phenyl-4F7-indeno[l,2- )]thiophene-4-one oxime 28 by reaction with hydroxylamine in the presence of sodium acetate, which underwent the Beckmann rearrangement upon treatment with polyphosphoric acid to give 2-phenylthieno[3,2-c]quinoline-4(5/f)one 29. ... 

Benz[b]indeno[2,l d]thiophenes by double ring closure... 

Solns. of o-bis(phenylethynyl)benzene and sulfur dichloride each in dry methylene chloride added simultaneously during 45 min, to stirred refluxing methylene chloride, and refluxing continued 15 min. 10-(a-dilorobenzylidene)benz[b]-indeno[2,l-d]thiophene. Y 90.3%. T.J. Barton, A. J. Nelson, and J. Clardy, J. Org. Chem. 36, 3995 (1971). 

Thiophen Analogues of Indene.—Quantitative data for the base-catalysed tautomerization of the 4-methyl- to the 6-methyl-4 T-cyclopenta[c]thipphen have been obtained. The tautomerization was about 10 times slower than that of 1-methylindene. 107f-Indeno[l,2-Z>][l]benzothiophen has been prepared by treating 2-phenylbenzo[6]thiophen-3-carboxaldehyde with sodium methoxide in hot bis(2-methoxyethyl) ether. ... 

Benzannulated enyne-allenes with heteroatomic substitution in the allene branch are precursors of the indeno-fused heteroatomic systems that are suitable for use in pharmacological applications. Introducing a heteratomic substituent in the allene branch of the enyne-allenes promotes a cascade of reactions that lead to derivatives such as 1 OH-indeno [1,2-g] quinoline, 9H-fluorene[2,3- ] furan, 9H-fluorene[2, 3-b]thiophene, 5H- and 6H-indeno[2,l-/]indolizine [278]. An example of this strategy is the synthesis of indeno-fused derivatives of quino-lizinium salts 3.558 (Scheme 3.41) [278]. 

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