5-Ethoxycarbonyl-1,2,3-triphenyl

Die reduktive Cyclisierung von Benzofuroxan mit (Ethoxycarbonyl-methylen)-triphenyl-phos-phan liefert nach einem komplizierten Mechanismus neben 2-Ethoxycarbonyl-benzimidazol (18%) l-Ethoxy-2-ethoxycarbonyl-benzimidazol (16%)186 ... 

Ethoxycarbonyl-l-hydroxy-benzimidazol wird offensichtlich auch bei der Umsetzung von Benzofurazan-l-oxid mit (Ethoxycarbonyl-methylen)-triphenyl-phosphoran als Zwischenpro-dukt durchlaufen nach weiterer Reaktion mit (Ethoxycarbonyl-methylen)-triphenyl-phospho-ran wird letztlich ein Gemisch aus J-Ethoxy-2-ethoxycarbonyl- und 2-Ethoxycarhonyl-henz-imidazol erhalten299. 

AMIDES N-Ethoxycarbonyl-2-ethoxy-l,2-dihydroquinoline (EEDQ). Silicon tetrachloride. Sodium hydride-Dimethylsulf-oxide. Triphenyl phosphite. 

PEPTIDE SYNTHESIS Diphenylphosphoryl azide. N-Ethoxycarbonyl-2-ethoxy-l, 3-di-hydroquinoline. o-Nitrophenylsulfenyl chloride. 2-Picolyl chloride hydrochloride. Silicon tetrachloride. Triphenylphosphine. Triphenylphosphine-Carbon tetrachloride. Triphenyl phosphite. 

Dioxo-l-ethoxycarbonyl-3-(2-trimethylsilyl-cydopropyl)-prop-ylidenej-triphenyl- 814... 

Two other procedures for the synthesis of phosphoranimines have been described, which are totally different from the Staudinger approach. Microwave irradiation of a mixture of l-aryl-4-ethoxycarbonyl-5-amino-l,2,3-triazoles(10), PPh3 and EtsN in C2CI6 provides the corresponding 5-phosphoraniminato derivatives (11) in excellent yields. A chiral A-phosphine substituted phos-phoranimine (13) has been prepared by deprotonation of cyclopropyl(triphenyl)phosphonium bromide (12) with NaNH2 via a complicated reaction mechanism. ... 

PEPTIDE SYNTHESIS r-Amyl chloro-formate. f-Butyl azidoformate. Diethyl methyleneraalonate. N-Ethoxycarbonyl-2-ethoxy-l,3-dihydroquinoline. Hexamethylphosphoric triamide. 1-Hydroxybenzo triazole. Triphenylphosphine—2,2 -Dipyridyl disulfide. Triphenyl phosphite. 

Bei der Umsetzung von N-(2,3,4,5,6-Pentaacetoxy-thiohexanoyl)-acetamid mit (Ethoxycarbonyl-methyli-den)-triphenyl-phosphoran wird in niedriger Ausbcute 2-( 1,5-Diacctoxy-l,3-pentadien-y )-5-etht>xyi arbo-nyl-4-melhyl-l 3-thiazol (18%) erhalten756. Der Mechanismus dieser offensiehllich komplexen Reaktion ist noch ungeklart. 

Oxocyclohexylidene)triphenylphosphorane 456 [5-(Ethoxycarbonyl)pentyl]triphenyl-phos-phonium iodide (42 g) is added to a solution of potassium (3.4 g) in tert-butyl alcohol (300ml), and the mixture is heated under reflux for 12 h and then evaporated in a vacuum. The residue is shaken with chloroform and water. The chloroform layer is separated and dried, and the ylide is precipitated by ethyl acetate it has m.p. 243-245° (22.1 g, 79%). 

Substituierte 2H-Pyrone erhalt man in geringen Ausbeuten ( 20%) bei der Reaktion von 1,3-Diketonen mit (Ethoxycarbonyl-methylen)-triphenyl-phosphoran372. 

Aliphatic or aromatic aldehydes react with (ethoxycarbonyliodomethyl)triphenyl-phosphorane (183) in the presence of potassium carbonate in a two-phase liquid-solid system to give acetylenic esters 184 . Pyrolysis of a-halophosphoranes 185 (X = Cl or Br R = Ar or t-Bu) results in 1-haloalkynes 186. Vacuum pyrolysis of the betaine 188, formed from the phenoxymethylenephosphorane 187, yields the acetylenic ether 189 Flash-vacuum pyrolysis of the phosphorane 190 at 750°C gives triphenylphosphine oxide and phenylacetylene with elimination of the ethoxycarbonyl groups... 

Phosphoranes failed even in refluxing toluene to undergo Wittig olefination of lactones, unlike other carbonyl compounds. However, under MWI for 90 s, lactone 102 reacted with ethoxycarbonyl methylidene triphenyl phosphorane on mixing a 1 1.2 ratio to give 104 and 105. Similarly, 103 gave 106 and 107 after MWI for 110 s, each as a mixture of isomers in 80-82% yields. The EjZ product ratio was 20/80 for 104 and 105 and 15/85 for 106 and 107 (Scheme 21) (99TL165). 

C4 8H4 7BF4O6P2, Triphenyl-(l-ethoxycarbonyl-2-methyl-2 hydroxyvinyl)-phosphonium triphenyl-(1-ethoxycarbonyl-2-methyl-2-olatovinyl)phos-phonium tetrafluoroborate, 45B, 767... 

Reaction of 3-acetamido-3-deoxy-4,5 6,7-di-0-isopropylidene-2-0-methyl-a/dle/i> dlo-D-g/yccro-D-gfl/flcro-heptose with [ethoxy(ethoxycarbonyl)methylene]-triphenyl-phosphorane, followed by an ethoxymercuration-demercuration reaction and acid hydrolysis resulted in the formation of the ethyl esters of 4-0-methyl-N-acetylneuraminic acid and 4-0-methyl-4-epi-N-acetylneuraminic acid (Beau et al. 1978). By oxymercuration of ethyl 5-acetamido-3,5-dideoxy-2-0-ethyl-4-0-methyl-D-g/jcero-D-ga/acto-non-2-enonate with mercury(II) trifluoroacetate, followed by borohydride-demercuration, 4-0-methyl-N-acetylneuraminic acid ethyl (3-glycoside was obtained (Beau et al. 1980). 4-0-Methyl-N-acetylneuraminic acid has been used in metabolism studies, as reported by Beau and Schauer (1980). Using tritiated sodiumborohydride, the corresponding 4-0-methyl-N-acetyl-[3-3H]neuraminic acid was obtained (Beau and Schauer 1980). 

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