Furan tetrahydro- from

Functional tests, for enzyme purity, 286 Fungi, polysaccharides of, 367—417 2-Furaldehyde, 5-(hydroxymethyl)-, from cellulose on pyrolysis, 432 Furan, tetrahydro-, as solvent in lithium... 

Furfural — see Furan-2-oarbaldehyde, 532 Furfuryl acetate, o -(butoxycarbonyl)-anodic oxidation, 1, 424 Furfuryi acrylate polymerization, 1, 279 Furfuryl alcohol configuration, 4, 544 2-Furfuryl alcohol polyoondensation, 1, 278 reactions, 4, 70-71 Furfuryl alcohol, dihydro-pyran-4-one synthesis from, 3, 815 Furfuryl alcohol, tetrahydro-polymers, 1, 276 rearrangement, 3, 773 Furfuryl chloride reactions... 

Examples of mono-layer adsorption isotherms obtained for chloroform and butyl chloride are shown in Figure 5. The adsorption isotherms of the more polar solvents, ethyl acetate, isopropanol and tetrahydro-furan from -heptane solutions on silica gel were examined by Scott and Kucera [4]. Somewhat surprisingly, it was found that the experimental results for the more polar solvents did not fit the simple mono-layer... 

The 17a-ethynyl compound (59) has been prepared in 88% yield from estr-4-ene-3,17-dione (58) and acetylene, at 2-3 atm pressure in tetrahydro-furan in the presence of potassium t-butoxide. Presumably the A-ring enone system is protected as the enolate anion during the course of the reaction. 

Detailed mechanistic studies101 indicate that benzazepines arc formed by 1,7-electrocyclization of a nitrile ylidc intermediate followed by a [l,5]-sigmatropic hydrogen shift in the initially formed 9a//-2-benzazepine. Similar products, e.g. 9, have been obtained by generating the nitrile ylide 8 from the imidoylchloride, e.g. 7. with potassium /ert-butoxide in tetrahydro-furan.101... 

Solutions containing approximately 1.6JH butyllithium in hexane were purchased either from Alfa Inorganics, Inc., or from Foote Mineral Company, The concentration of butyllithium in these solutions can be determined either by a double titration procedure2 or by dilution with anhydrous tetrahydro furan followed by titration with 2-butanol in the presence of a 2,2 -bipyridyl indicator.3 In either ease the total base concentration in the reagent is determined by titration with standard aqueous acid. 

The Cu(I)-catalyzed cyclization for the formation of ethyl ( )-tetrahydro-4-methylene-2-phenyl-3-(phenylsulfonyl)furan-3-carboxylate 82 has been accomplished starting from propargyl alcohol and ethyl 2-phenylsulfonyl cinnamate. Upon treatment with Pd(0) and phenylvinyl zinc chloride as shown in the following scheme, the methylenetetrahydrofuran 82 can be converted to a 2,3,4-trisubstituted 2,5-dihydrofuran. In this manner, a number of substituents (aryl, vinyl and alkyl) can be introduced to C4 <00EJO1711>. Moderate yields of 2-(a-substituted N-tosyIaminomethyl)-2,5-dihydrofurans can be realized when N-tosylimines are treated with a 4-hydroxy-cis-butenyl arsonium salt or a sulfonium salt in the presence of KOH in acetonitrile. The mechanism is believed to involve a new ylide cyclization process <00T2967>. 

In the reaction of EMME and the potassium salt of pyrrole in tetrahydro-furan (THF) at 0°C for 30 min, an addition product, ethoxy(l-pyrrolyl)-methylmalonate (115), could be isolated in 85% yield (82CB714). This ester (115) was hydrolyzed with potassium hydroxide in aqueous ethanol at reflux temperature to yield 95% dipotassium ethoxy( 1 -pyrrolyI)methylene-malonate (116), from which 1-pyrrolylmethylenemalonic acid (118) was... 

The most recent entrant-to the. club of commodity chemicals is 1,4-butanediol (BDO), a petrochemical used in some of the more specialized applications such as chemical intermediates for the production of tetrahydro-furane and gama-butyrolactone, polybutylene terephthalate, and the more familiar polyurethanes. Traditionally, the Reppe process was the primary route to BDO, based bn acetylene and formaldehyde feeds. More recently, the share of BDO from butane and propylene oxide based production has grown rapidly. 

An example of octahedral Sc(III) complex with nonidentical ligand is presented by Atwood and Smith (46) for trichloro-tris-tetrahydrofm an-Sc(III), [ScCl3(C4 H80)3], which crystallizes as monoclinic plates (P2i/c, Z=4) from tetrahydro-furan. The pale pink colour described by these authors (46) is somewhat doubtful for a cationic Sc(III) complex and may have been caused by the presence of some reducing agent as impurity in THF. The cell parameters are a = 8.890, b —12.842, c = 15.485 A and / =92.24°. 

Titanium in a low valence state, as prepared by treatment of solutions of titanium trichloride with potassium [206] or magnesium [207] in tetrahydro-furan or with lithium in dimethoxyethane [206], deoxygenates ketones and effects coupling of two molecules at the carbonyl carbon to form alkenes, usually a mixture of both stereoisomers. If a mixture of acetone with other ketones is treated with titanium trichloride and lithium, the alkene formed by combination of acetone with the other ketone predominates over the symmetrical alkene produced from the other ketone [20(5] Procedure 39, p.215). 

Aldehydes are obtained in 86% and 75% yields, respectively, from benzoic acid on refluxing for 6 hours and from nicotinic acid on standing at room temperature for 24 hours with bis(N-methylpiperazino)alane in tetrahydro-furan [963]. Reduction of 3-fluorosalicylic acid with 2% sodium amalgam in aqueous solution containing sodium chloride, boric acid and p-toluidine gave, at 13-15°, a Schiff base which on hydrolysis with hydrochloric acid and steam distillation afforded 3-fluorosalicylaldehyde in 57% yield [136. The purpose of p-toluidine is to react with the aldehyde as it is formed and protect it from further reduction. 

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