Lithium ethylenediamine

Dehydrogenation of dipentene (d,l-limonene) and 4-vinylcyclohexene has been studied using both the lithium-ethylenediamine catalyst system (4) and the sodium-alumina catalyst system (12). The aromatic compounds p-cymene and ethylbenzene are produced by both types of catalyst however, while vinylcyclohexene yields ethylbenzene rapidly at 0° over a sodium on alumina catalyst, dipentene yields mainly mixed dienes at 0 but at 25 is also rapidly dehydrogenated to p-cymene (12). 

The discovery that sodium in the presence of small amounts of organosodium compounds, produced in situ or deposited on alumina, acts as an effective catal for double bond isomerization of alkenes and cyclenes U) triggered much research in this field (2). It was subsequently discovered that base-catalyzed isomerization of olefins may proceed in homogeneous solutions using lithium ethylenediamine (3) or potassium tert-butoxide (UBuOK) in dimethyl sulfoxide (DMSO) (4). 

REDUCTION, REAGENTS Bis(triphenyl-phosphine)copper tetrahydroborate. Borane-Pyridine. Calcium-Methylamine/ ethylenediaminc. Chlorobis(cyclopenta-dienyl)tetrahydroboratozirconium(IV). Chromium(II)-Amine complexes. Copper(0)-lsonitrile complexes. 2,2-Dihydroxy-l, 1-binaphthyl-Lithium aluminum hydride. Di-iododimethylsilane. Diisobutyl-aluminum 2,6-di-/-butylphenoxide. Diisobutyl aluminum hydride. Dimethyl sulfide-Trifluoroacetic anhydride. Disodium tetracarbonylferrate. Lithium-Ammonia. Lithium-Ethylenediamine. Lithium bronze. Lithium aluminum hydride. Lithium triethylborohydride. Potassium-Graphite. 1,3-Propanedithiol. Pyridine-Sulfur trioxide complex. 

In this connection, it may be mentioned that the side-chain in cycloartenol (489) has been degraded to the androstan-17-one (490) and progest-20-one (491) analogues. This was achieved by migration of the C(24)-C(25) double bond to the C(17) and C(20) positions under the influence of lithium ethylenediamine. 

Reducing agents Aluminum hydride. Bis-3-methyl-2-butylborane. n-Butyllithium-Pyridine. Calcium borohydride. Chloroiridic acid. Chromous acetate. Chromous chloride. Chromous sulfate. Copper chromite. Diborane. Diborane-Boron trifluoride. Diborane-Sodium borohydride. Diethyl phosphonate. Diimide. Diisobutylaluminum hydride. Dimethyl sulfide. Hexamethylphosphorous triamide. Iridium tetrachloride. Lead. Lithium alkyla-mines. Lithium aluminum hydride. Lithium aluminum hydride-Aluminum chloride. Lithium-Ammonia. Lithium diisobutylmethylaluminum hydride. Lithium-Diphenyl. Lithium ethylenediamine. Lithium-Hexamethylphosphoric triamide. Lithium hydride. Lithium triethoxyaluminum hydride. Lithium tri-/-butoxyaluminum hydride. Nickel-aluminum alloy. Pyridine-n-Butyllithium. Sodium amalgam. Sodium-Ammonia. Sodium borohydride. Sodium borohydride-BFs, see DDQ. Sodium dihydrobis-(2-methoxyethoxy) aluminate. Sodium hydrosulflte. Sodium telluride. Stannous chloride. Tin-HBr. Tri-n-butyltin hydride. Trimethyl phosphite, see Dinitrogen tetroxide. 

Tetramethyl-la,2,3,4,6,7,8,8a-octahydrobenzofuro[4,3,2-fr,c,d]benzo-furan 604 was obtained in a one-pot reaction of 1 with lithium ethylenediamine(Li/EDA), through the enolization of dimedone in the alkaline medium to give the dienol, which underwent dehydration to the diether 602. The latter formed two free-radical sites at 2,2 -positions upon attack by the nascent hydrogen formed by Li/EDA, which led to the formation of a C-C bond to give the intermediate 603 that on isomerization furnished 604 (92IJC(B)762) (Scheme 128). 

Reactions with lithium ethylenediamine Migration of carbon-carbon double bonds... 

Cl2H26CI2CU2N4O14, Bis(perchlorato(2-(2-hydroxyethyl)imino-3-oximo-butanato)aquocopper(II)), 40B, 971 Cl2H2sCrLiN20i3, Lithium ethylenediamine-N,N -diacetato-N,N di-3-propionatochromatedll) pentahydrate, 43B, 1139 C12H2 6 9 2N2O.4, 1,4,10,1 3-Tetraoxa-7,16-diazacyclooctadecanemercury-(II) diiodide, 45B, 1248... 

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