Naphtho 2,3-c furan

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

Benz-annelatedbenzo[c]furandiones—naphtho[2,3-c]furan-4,9-diones— (Table XIII) were prepared in moderate to good yields by a Friedel-Crafts... 

Wege and Moursounidis found that a linear Herndon relationship (log k vs log SC 82JCE371) is obeyed. Extrapolation to naphtho[2,3-c]furan gives ki = 3.15 x 104 mol-1 s-1, which is 415 times greater than the reactivity of isobenzofuran 2. The effects of substituents in isobenzofuran on a Diels-Alder reaction (with A-methylmaleimide, which gives nearly exclusively endo-adducts) was quantified by Rickborn and co-workers (Table III ... 

Linear benz-annelation enhances the reactivity and decreases the stability of benzo[c]furan, as with other o-quinonoid heterocycles. 1,3-Diphenyl-naphtho[2,3-c]furan (299) has been obtained from 297 via lactol 298 as deep red glistening plates with mp 148-154°C in 89% yield. Although dried crystals of 299 could be stored for several months in the absence of light and air, solutions in organic solvents decolorized slowly on standing... 

Sikkimotoxin, 3a,4,9,9a-Tetrahydro-4-hydroxy-6,7-dunethoxy-9-(3,4,S-trimethoxyphenyt)naphtho 2,3-c -furan-I(3H) >ne 1 -hydroxy-2-hydroxymethyl-6,7-dimeth -oxy-4-(3 4 5 -trim ethoxy phenyl)-1,2,3,4-let rahydro-naphthalene-3-carboxylic acid lactone, C Hj p, mol wt 430.44. C 64.17%, H 6.09%, O 29.74%. Isoln from roots and rhizomes of Podophyllum sikkimeitsis R. Chatterjee et Mukerjee, Berberidaceae Chatterjee. Datta, Indian J. Physiol Allied Set 4, 6l (1950). Structnre Chatterjee. Chakra-varti, J. Am. Pharm. Assoc. Scl Ed. 4l, 415 (1952) Schreier, Helv. Chim. Acta 47, 1529 (1964). 

Naphtho[2,3-c]furan-1,3-dione 2,3-Naphthalenedicarboxylic acid anhydride Ci2Hg03 716-39-2 198.174 246 si EtOH, chi s eth, bz... 

Naphtho[2,3-c]furan-4,9-diones and related compounds 05T9929. 

Naphtho[2,3-6]thiophene-2,3-dione, N-70014 Naphtho[2,3-c]furan-l,3-dione, in N-80001... 

Hydroxyacenaphthylene, H-70100 Naphtho[l,2-c]furan, N-70008 Naphtho[2,3-c]furan, N-60008 Naphtho[l,8-6c]pyran, N-70009 1 -Phenyl-1,4-hexadiyn- 3-one, P-60108... 

Reaction with Quinones and Naphthoquinones. Naphth-acene-5,12-diones and naphtho[2,3-c]furan-4,9-diones can be obtained by Mn(OAc)3-promoted reaction between 2-benzoyl-1,4-naphthoquinones and 1,3-dicarbonyls (eq 32). Electron-withdrawing groups on the benzoyl moiety will favor the naph-thofurane derivatives. Higher selectivity is also observed as the size of the 1,3-dicarbonyl substituent (R) increases. Naphthofu-ranes will also be favored in neutral solvents or if the reagents are heated with sodium acetate prior to the reaction with Mn(OAc)3. In contrast, naphthacenediones will be favored if the reaction is carried out in formic acid. An intramolecular variant of this reaction exists and furnishes the naphthacenediones in higher yield, only trace amounts of naphthofuranes are observed (eq 33). ... 

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