Naphtho thiophene

Naphtho[2,3-c]furan, 1,3-diphenyl-thiophene synthesis from, 4, 904 Naphthofurans aromaticity... 

Naphtho[2,3-h]thiophene, S-methyl-theoretical methods, 4, 3 Naphtho[2,3-c]thiophene, 1,3-diphenyl-synthesis, 4, 904... 

Naphtho[ 1,2-h]thiophene-2-carboxylic acid synthesis, 4, 893 Naphthothiophenes synthesis, 4, 881, 907, 914 Naphthothiophenes, dihydrosynthesis, 4, 113 Naphtho[ 1,2-c]thiophenes synthesis, 4, 891 Naphtho[2, l-h]thiophenes synthesis, 4, 907 Naphtho[2,3-h]thiophenes synthesis, 4, 905, 908-909 Naphtho[ 1,8-de][l,2,3]triazine, 2-methyl-reactions... 

Armulated thiophenes of types 195 and 197 (A benzo, naphtho) were studied concerning keto-enol tautomerism. The ring fusion has a remarkable influence upon these equilibria. Whereas for the c-fused thiophenes 197 only keto tautomers were present, for h-fused derivatives 195 also the enol forms 196 were found (the equilibria are solvent dependent) (82JOC705). 

The oxidation of benzo[( ]thiophene by strains of pseudomonads produces the sulfoxide that undergoes an intramolecular Diels-Alder reaction followed by further transformation to benzo[fc]naphtho[l,2- (]thiophene (Figure 2.2b) (Kropp et al. 1994). 

In addition, the formation of terminal metabolites may be adverse either for the organism itself, or for other organisms in the ecosystem. Microbial metabolites may also undergo purely chemical reactions to compounds that are terminal products. Examples include the formation of 5-hydroxyquinoline-2-carboxylate from 5-aminonaphthalene-2-sulfonate (Nortemann et al. 1993) or benzo[fc]naphtho[l,2- /]thiophene from benzothiophene (Kropp et al. 1994). Microbial metabolites may be toxic to both the bacteria producing them and to higher organisms. Illustrative examples of toxicity include the following ... 

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. 

Thiophene Benzothiophene (BT) Dibenzothiophene (DBT) Benzo(a)naphtho(2,3-d)thiophene Nitrogen compounds... 

The second Mycobacterium strain capable of DBT desulfurization was M. phlei WU-F1 [30], This strain was also reported to desulfurize naphtho[2,l-b]thiophene (NTH) and 2-ethyl-NTH to sulfur free products with the following intermediates for the latter molecule 2-ethyl-NTH sulfoxide, l-(2 -hydroxynaphthyl)-l-butene, and l-naphthyl-2-hydroxy-1-butene [94], Thus, this organism was reported to consist of a sulfur-specific pathway capable of desulfurization of broad range of sulfur compounds including symmetric and asymmetric molecules. 

Watanabe, K. Noda, K., and Maruhashi, K., Selective cleavage of 10-methyl benzo b naphtho 2,1-d thiophene by recombinant Mycobacterium sp strain. Biotechnology, Letters, 2003. 25(10) pp. 797-803. 

First examples of stable carbocations were reported from several classes of thia-PAHs with four fused rings, namely, benzo[Z ]naphtho[2,l-J thiophene (40) and its 3-methoxy derivative (41), phenanthro[4,3-Z ]thiophene (42) and its 7-methoxy (43), 10-methoxy (44), and 9-methoxy (45) derivatives, phenanthro[3,4-Z ]thiophene (46) and its 7-methoxy (47) and 9-methoxy (48) derivatives, and 3-methoxybenzo[Z ]-naphtha[l,2-J thiophene (50) (Fig. 25). Regioselectivity issues and charge... 

Castle and co-workers <1996JHC119, 1996JHC185, 1997JHC1597, 1998JHC1441> used 3-chlorothieno [2,3-3]thiophene-2-carbonyl chloride 280 in the synthesis of the appropriate amides, which by oxidative photo-cyclization gave novel polycyclic heterocyclic ring systems thieno[3, 2 4,5]thieno[2,3-f][l,10]phenanthroline 281, thieno[3, 2 4,5]thieno[2,3-f]naphtho[2,iy ]quinoline 282 and thieno[3, 2 4,5]thieno[2,3-f]naphtho[l,2-g]qui-noline 283, thieno[3, 2 4,5]thieno[2,3-f]naphtho[l,2y ]quinoline 284, thieno[3, 2 4,5]thieno[2,3-f]naphtho[l,2 7]-[l,2,4]triazolo[3,4- ]quinoline 286, thieno[3, 2 4,5]thieno[2,3-f]naphtho[l,2-/]tetrazolo[l,5- ]quinoline 288, benzo[ ]thieno[3, 2 4,5]thieno[2,3-f]quinoline 285, benzo /]thieno[3, 2 4,5]thieno[2,3-f]quinoline 287, benzol/] thieno[3, 2 4,5]thieno[2,3-f]tetrazolo[l,5- ]quinoline 289, and benzo[/jthieno[3, 2 4,5]thieno[2.3-f][l,2,4]triazolo[4,3- ]-quinoline 290. 

Fig. 29. Correlation between relative hydrogenolysis reactivity and the electron densities on sulfur. ( ) Reaction conditions 300°C, 71 atm, sulfided CoO-Mo03/A1203 (5). (1) DBT (2) benzo[fo]naphtho[2,3-4]thiophene (3) 7,8,9,10-tetrahydrobenzo[b]naphtho[2,3-rf]thio-phene (4) 5b,6,ll,lla-tetrahydrobenzo[fc]naphtho[2,3-d]thiophene. (O) Reaction conditions 450°C, 1 atm, sulfided CoO-Mo03/A1203(6). (5) Thiophene (6) tetrahydrothiophene (7) benzothiophene (8) 2,3-dihydrobenzothiophene. ( + ) Reaction conditions 360°C, 2.9 MPa, sulfided NiO-Mo03/Al203(3). (9) 1-Methyl-DBT (10) 2- or 3-methyl-DBT (11) 4-methyl-DBT (12) 4,6-dimethyl-DBT. (A) Reaction conditions 300°C, 102 atm, sulfided CoO-Mo03/ Al203(8). (13) 2,8-Dimethyl-DBT (14) 3,7-dimethyl-DBT (15) 4-methyl-DBT (16) 4,6-di-methyl-DBT. Reprinted with permission from Ref. 38, Ma et al. (1995). Copyright 1995 American Chemical Society.

The Vilsmeier-Haack reaction of ketones forms chlorovinyl aldehydes, which can add thiols readily. The reaction with a-tetralone gave the chlorovinyl aldehyde (230), and reaction with ethyl thioglycolate in ethanolic ethoxide solution formed the dihydro derivative (231), easily dehydrogenated to naphtho[l,2-6]thiophene-2-carboxylate (73JCS(P1)2956). 

Naphtho[2,3-b jthiophene derivatives (316) have been synthesized by this scheme, starting with phthalic anhydride, which could be reacted with thiophene under Friedel-Crafts conditions to give (315) (52JA4353). By the same scheme, anthra[2,3-bjthiophene (318) was obtained from (317) in 51% yield, by reduction of the acid to aldehyde and cyclization in PPA (81JHC967). 

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