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Pyridine tetrakis

Tetrakis-(N-dihyciropyridyl)-aluininate, see Lithium aluminum hydride-Pyridine. Tetrakis-phosphorus trichloride-nickel (0), Ni(PCla)4- Preparation. ... [Pg.574]

In extending this direct method of synthesis, we next investigated the possibility of preparing similarly constituted halides from 2-deoxy-D-arabino-hexose (2-deoxy-D-glucose) (21). The hexose was subjected to a partial anomerization procedure described by Bergmann and co-workers (1). The solid material obtained by this procedure is a mixture of the anomeric forms of 2-deoxy-D-arabino-hexose low temperature p-nitro-benzoylation of the latter in pyridine resulted in a mixture of crystalline, anomeric tetrakis-p-nitrobenzoates in a ratio of approximately 1 1. They were readily separable by fractional recrystallization, and treatment of either with an excess of hydrogen bromide in dichloromethane, or with... [Pg.11]

Natriumboranat/Pyridin > Lithium-tetrakis-[l,2-dihydro-pyridyl-(l)]-aluminat > Natriumboranat/Alkohol > Lithium-tri.-tert.-butyloxy-hydrido-aluminat > Lithiumalanat > Lithium-trimethoxy-hydrido-aluminat > Aluminiumhydrid > Bis-[2-methyl-propyl]-aluminiumhydrid... [Pg.299]

In Gegenwart von Tetrakis-[pyridin]-nickel-diperchlorat oder Nickel(II)-chlorid in Athanol mit Tetrabutylammonium-perchlorat als Leitsalz erhalt man unter partieller Hy-drierung und Oligomerisation aus Butadien-(1,3) all-trans-Hexadecatetraen-(1,6,10, J4) in Gegenwart von Bis-[triphenylphosphin]-nickel(II)-chlorid wird Octatrien-(l,3,7) er-halten4. [Pg.580]

One of the earliest syntheses of lavendamycin methyl ester, however, did not employ either the Pictet-Spengler or the Bischler-Napieralski reactions for construction of the /J-carboline ring system. Instead, a palladium-promoted ring closure of aryl pyridine 36 (Fig. 12) was used to prepare /1-carboline 37 by Boger and coworkers [35]. Unfortunately, stoichiometric palladium was found to be necessary, in this case 1.5 equivalents of the tetrakis(triphenylphosphine)palladium(0) being used. Friedlander condensation with aldehyde 38 in the presence of benzyltrimethylammonium hydrox-... [Pg.114]

Several pyridine containing ligands of this type have been reported by Toftlund [2]. A combination of two aliphatic and four imine nitrogen functions seems to provide a ligand field at the crossover point. A versatile class of ligands of this type is based on aliphatic diamines substituted with four alkylpyridine groups. The simplest compound of this type is tetrakis(2-pyri-dylmethyl)-l,2-ethanediamine (tpen) (18). [Pg.174]

A useful method for the synthesis of 1-unsubstituted 2-arylindolizines is provided by the 1,5-dipolar cyclization of pyridinium ylides derived from 181, in the presence of the oxidant tetrakis(pyridine)cobalt(ll) dichromate (TPCD), which oxidizes the intermediate dihydroindolizine 182 (Scheme 43). The study demonstrated that the presence of an aryl group on the double bond was necessary for the reaction to occur. [Pg.385]

Lithium aluminum hydride dissolves in pyridine and forms lithium tetrakis-(A -dihydropyridyl)aluminate which itself is a reducing agent for purely aromatic ketones [440, 441]. [Pg.55]

Heteroaromatics are subdivided, according to the electron influence of the heteroatom, into w-electron-deficient compounds and compounds with an excess of it electrons on the ring carbon atoms. The typical ff-electron-delicient compound pyridine has so far been made to react only in one case the reaction of lithium tetrakis(A-dihydropyridyl)-aluminate (LDPA) [112-114), obtainable from pyridine and lithium aluminum hydride, with trifluoromethanesulfenyl chloride in an excess of pyridine affords 3-trifluoromethylmercaptopyridine in low yield (13%) (60). This reaction probably occurs through sulfenylation of the l,2-dihydrop5T idyl moiety of the LDPA with the formation of a 2,5-... [Pg.180]

The 1,3-dipolar addition of ylide 223 with various dipolarophilic alkenes to produce 224 after aromatization of the adducts was reported to proceed significantly more selectively in the presence of MnOz than in the original reaction where TPCD (tetrakis(pyridine) cobalt(II) dichromate) was used as the oxidant in which 224 were minor by-products <99JCR(S)552>. [Pg.291]

MoC8K4Ng-2H20, Molybdate(IV), octacyano-, potassium, dihydrate, 34 157 M0N3O3C18H15, Molybdenum(O), tricarbonyl-tris(pyridine)-, 34 104 M0N11C56H108, Molybdate (V), octacyano-, tetrabutylammonium, 34 158 M04O16RU4C40H56, Molybdate(VI), tetrakis rj -l-isopropyl-4-methylbenzene)rutheniu-m(II)-, 34 200... [Pg.250]


See other pages where Pyridine tetrakis is mentioned: [Pg.64]    [Pg.13]    [Pg.122]    [Pg.137]    [Pg.149]    [Pg.497]    [Pg.259]    [Pg.383]    [Pg.630]    [Pg.678]    [Pg.972]    [Pg.1017]    [Pg.1217]    [Pg.1217]    [Pg.1291]    [Pg.298]    [Pg.398]    [Pg.45]    [Pg.81]    [Pg.82]    [Pg.141]    [Pg.248]    [Pg.303]    [Pg.328]    [Pg.654]    [Pg.684]    [Pg.62]    [Pg.239]    [Pg.67]    [Pg.1019]    [Pg.34]    [Pg.397]    [Pg.327]    [Pg.139]    [Pg.43]    [Pg.43]    [Pg.1019]   
See also in sourсe #XX -- [ Pg.4 , Pg.1032 ]




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