Furan 2.5- dihydro-2,5-dimethoxy

Furan, 2,5-dihydro-2,5-dimethoxy-13C NMR, 4, 573 heat of hydrogenation, 4, 592 Furan, 2,5-dihydro-3,4-dimethylene- H NMR, 4, 577 Furan, 2,3-dihydro-3-hydroxy-synthesis, 4, 685 Furan, 2,3-dihydro-5-lithio-13C NMR, 4, 572 Furan, 2,3-dihydro-3-methyl- H NMR, 4, 570... [Pg.630]

Furans with bulky a-substituents such as 2-rerf-butylfuran [176] and 2-acetoxy-furan dimethyl acetal [177] show no effect of steric hindrance and are readily converted to the dihydro-dimethoxy product. 3,4-Substituted furans are also converted to dihydrodimethoxy derivatives [178, 179],... [Pg.223]

Benzo[c]furan, 1-/-butyl-l,3-dihydro-5,6-dimethoxy- H NMR, 4, 574 <75JA5160>... [Pg.8]

Benzo[c]furan, 1,3-dihydro-1 -phenyl- H NMR, 4, 574 <75JA5160> Benzo[b]furan-2-carbaldehyde, 3,6-dimethoxy-UV, 4, 589 <71AJC1883> Benzo[b]furan-2-carbaldehyde, 3-methoxy-UV, 4, 589 <73AJC1079>... [Pg.8]

Benzo[b]furan, 2,3-dihydro-2-phenyl-synthesis, 4, 697 Benzo[b]furan, 2,3-dihydroxy-tautomerism, 4, 37 Benzo[6]furan, 4,6-dimethoxy-acylation, 4, 606 Benzo[6]furan, 2,3-dimethyl-acetylation, 4, 606 bromination, 4, 605 photooxygenation, 4, 642 Benzo[b]furan, 5,6-dimethyl-2,3-diphenyl-applications, 4, 709 Benzo[b]furan, 1,3-diphenyl-vertical ionization potential, 4, 587 Benzo[b]furan, 2-ethoxy-5-hydroxy-synthesis, 4, 127... [Pg.547]

Furan, 2,3-dihydro-5-methyl-polymers, 1, 276 Furan, 2,3-dihydro-3-methylene- H NMR, 4, 577 Furan, 2,5-dihydro-2-methylene- H NMR, 4, 577 tautomerism aromaticity and, 4, 595 Furan, 2,5-dihydro-2-nitro-structure, 4, 550 Furan, 2,3-dihydroxy-tautomerism, 4, 37 Furan, 2,4-dihydroxy-tautomerism, 4, 37 Furan, 3,4-dihydroxy-tautomerism, 4, 37 Furan, 2,5-diiodo-nitration, 4, 602 synthesis, 4, 712 Furan, 3,4-diiodo-reactions, 4, 650 Furan, 2,3-dimethoxy-synthesis, 4, 625, 648 Furan, 2,5-dimethoxy-synthesis, 4, 648 Furan, 3,4-dimethoxy-cycloaddition reactions, 4, 64, 625 lithiation, 4, 651 reactions... [Pg.630]

In connection with the anodic intramolecular coupling of 1-benzyltetrahydroiso-quinoline derivatives, the anodic oxidation of 4-(3,4-dimethoxybenzyl)-6,7-dimethoxy-isochromanone 15 has been studied rather extensively. The main product obtained from the isochromanone is a y-lactone, 7a,8-dihydro-3,10,ll-trimethoxy-2 H-phenanthro[9.8a, b]furan-2,7(5 H)-dione 16 13 ... [Pg.137]

In certain cases, a photochemical 2,5-oxidation can also be carried out. Wasserman and Liberies275 oxidized tetraphenylfuran in methanolic solution, by irradiation and treatment with atmospheric oxygen, and obtained 2,5-dimethoxy-2,3,4,5-tetraphenyl-2,5-dihydro-furan. In acetone the furan ring is cleaved ... [Pg.431]

Other syntheses involve the preparation from the monoacetate of the enolic form of nitrosuccindialdehyde/ or the dibenzoyldioxime of maleic aldehyde/ or by dehydrogenation of l-tosyl-l,4-dihydro-pyridazine. From 2,5-diacetoxy- or 2,5-dimethoxy-2,5-dihydro-furan pyridazine can be obtained in high yield. Maleic aldehyde has been obtained also when decomposing the adduct obtained in the Diels-Alder reaction between furan and diethyl azodicarboxylate and straightforward condensation with hydrazine afforded pyridazine in 55% yield.Another direct reaction involving maleic aldehyde... [Pg.213]

Furan 2,5-Dimethoxy-2-methoxy-carbonyl-2,5-dihydro- Vl/3, 712 Octandisaure 4-Oxo- VII/2b, 1327 Oxiran 2,2-Diethoxycarbonyl- Vl/3, 416... [Pg.516]

Amino-4-hydroxy-8-methyl- E19d, 689 (aus 1,3-Oxazol-Der.) 7-Aminoxy-4-methyl- El 6a, 264 Furan 3,4-Dihydroxy-5-imino-2-phenyl-2,5-dihydro- VI/2, 698 Glyoxylsaure (3,4-Dimethoxy-phenyl)- -nitril E13/2, 1158 (Alkohol - Keton)... [Pg.719]

E15/1, 1189 (H N02) 1-Benzofuran 5,6-Dimethoxy-2-hydroximino-3-oxo-2,3-dihydro-E6b/1, 114 (3-OH —1-benzo-furan + NaN02)... [Pg.719]

Furan, reaction with bromine and methanol to yield 2,5-dimethoxy-2,5-dihydrofuran, 40, 29 FuEAN, 2,5-DIHyDRO-2,5-DmETHOXY-,... [Pg.58]

Ring-opening and reclosure processes using furans include several significant methods for the constraction of pyridines. 2,5-Dihydro-2,5-dimethoxy-furans (see 18.1.1.4) carrying as a C-2 side-chain an aminoalkyl group, give rise to 3-hydroxy-pyridines. ... [Pg.164]

Methoxy- and 2-acetoxy-furans are available from 2,5-dimethoxy- and 2,5-diacetoxy-2,5-dihydro-furans (18.1.1.4) via acid-catalysed elimination. They undergo Diels-Alder cycloadditions the adducts can be further transformed into benzenoid compounds by acid-catalysed opening. 3,4-Dihydroxyfuran is undetectable in tautomeric equilibria between mono-enol and dicarbonyl forms the dimethyl ether behaves as a normal furan, undergoing easy a-electrophilic substitution, mono- or dilithiation at the a-position(s), and Diels-Alder cycloadditions. 2,5-Bis(trimethylsilyloxy)furan is synthesised from succinic anhydride it too undergoes Diels-Alder additions readily. Both furan-2- and -3-thiols can be obtained by reaction of lithiated furans with sulfur in each case the predominant tautomer is the thiol form. ... [Pg.358]

The anodic oxidation of furans in methanol was also carried out without an intentionally added electrolyte (Figure 12.11) [38, 39]. 2,5-Dimethoxy-2,5-dihydro-furan was obtained in 98% yield. The anodic methoxylation and acetoxylation of various organic compounds was also achieved using this system. [Pg.381]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...