Nickel sodium hydride, reductions

Association of sodium hydride and alkali alkoxides with nickel salts has been reported to be effective in many hydrogenations and selective reductions of organic halides (211, 221). 

Cyclododecene may be prepared from 1,5,9-cyclododecatriene by the catalytic reduction with Raney nickel and hydrogen diluted with nitrogen, with nickel sulfide on alumina, with cobalt, iron, or nickel in the presence of thiophene, with palladium on charcoal, with palladimn chloride in the presence of water, with palladium on barium sulfate, with cobalt acetate in the presence of cobalt carbonyl, and with cobalt carbonyl and tri- -butyl phosphine. It may also be obtained from the triene by reduction with lithium and ethylamine, by disproportionation, - by epoxidation followed by isomerization to a ketone and WoliT-Kishner reduction, and from cyclododecanone by the reaction of its hydrazone with sodium hydride. ... 

Another highly active non-pyrophoric nickel catalyst is prepared by reduction of nickel acetate in tetrahydrofuran by sodium hydride at 45° in the presence of tert-amyl alcohol (which acts as an activator). Such catalysts, referred to as Nic catalysts, compare with P nickel boride and are suitable for hydrogenations at room temperature and atmospheric pressure, and for partial reduction of acetylenes to civ-alkenes [49]. 

Hydrogenation using Raney nickel is carried out under mild conditions and gives cis alkenes from internal alkynes in yields ranging from 50 to 100% [356, 357, 358, 359, 360]. Half hydrogenation of alkynes was also achieved over nickel prepared by reduction of nickel acetate with sodium borohydride (P-2 nickel, nickel boride) [349,361,362] or by reduction with sodium hydride [49], or by reduction of nickel bromide with potassium-graphite [363]. Other catalysts are palladium on charcoal [364], on barium sulfate [365, 366], on... 

From epoxides by reduction Samarium(II) iodide, 270 Sodium hydride-Sodium /-amyloxide-Nickel(II) chloride, 281 Sodium hydride-Sodium /-amyloxide-Zinc chloride, 281... 

Sodium borohydride-Palladium chloride. Sodium borohydride-Rhodium(lII) chloride. Sodium borohydride-Tin(II) chloride. Sodium cyanoborohydride. Sodium 9-cyano-9-hydrido-9-borabicyclo[3.3.1]nonane. Sodium dithionite. Sodium hydride-Sodium t-amyl oxide-Zinc chloride. Sodium trimethoxyborohydride. Tetra-/i-butylammonium borohydride. Tetra-n-butylammonium cyanoborohydride. Tetra-n-butylammonium octahydrotriborate. Tri-n-butyltin hydride. Triethoxy silane. Triisobutylaluminum-Bis(N-methyl-salicyclaldimine)nickel. Zinc borohydride. REDUCTIVE CYCLIZATION Cobaloximc(I). 

REDUCTION, REAGENTS Bis(N-methylpi-perazinyl)aluminum hydride. Borane-Di-methyl sulfide. Borane-Tetrahydrofurane. Borane-Pyridine. n-Butyllithium-Diisobu-tylaluminum hydride. Calcium-Amines. Diisobutylaluminum hydride. 8-Hydroxy-quinolinedihydroboronite. Lithium aluminum hydride. Lithium 9-boratabicy-clo[3.3.1]nonane. Lithium n-butyldiisopro-pylaluminum hydride. Lithium tri-j c-butylborohydride. Lithium triethylborohy-dride. Monochloroalane. Nickel boride. 2-Phenylbenzothiazoline. Potassium 9-(2,3-dimethyl-2-butoxy)-9-boratabicy-clo[3.3.1]nonane. Raney nickel. Sodium bis(2-methoxyethoxy)aluminum hydride. Sodium borohydride. Sodium borohy-dride-Nickel chloride. Sodium borohy-dride-Praeseodymium chloride. So-dium(dimethylamino)borohydride. Sodium hydrogen telluride. Thexyl chloroborane-Dimethyl sulfide. Tri-n-butylphosphine-Diphenyl disulfide. Tri-n-butyltin hydride. Zinc-l,2-Dibromoethane. Zinc borohydride. 

Reduction of nickel acetate with sodium hydride gave a nickel black catalyst that was active for the selective hydrogenation of acetylenes and dienes to the monoolefins. It was also capable of promoting the hydrogenation of carbonyl... 

Graham and Williams9 found nickel-aluminum alloy with aqueous sodium hydroxide to be a useful reagent for the reduction of ketoximes to amines without rearrangements that often accompany aluminum hydride reductions. 

Sulfones are useful organosulfur compounds.328 jn Pickett s synthesis of 9-methylgermacrene-B, sulfone 318 was treated with n-butyllithium to generate the a-carbanion.229 Alkylation with the allylic chloride shown gave 319.330 Hydrolysis of the acetate to an alcohol was followed by treatment with a palladium catalyzed Super-Hydride reduction of the sulfone to give 320 in 82% yield. Alternatively, sodium amalgam and Raney nickel [Ni(R)] can be used to remove sulfur from organic molecules (sec. 4.9.D). 331... 

This preparative method is one having the most general utility. It utilizes in situ reduction of suitable vicinal trans-nzido sulfonates to intermediary amino sulfonates, which undergo base-induced cyclization to epimines. Elevated temperatures are often required to complete the cyclization. The reduction by hydrazine with Raney nickel originally used was later largely replaced by lithium aluminum hydride reduction in tetrahydrofuran or diethyl ether. Re-duction by sodium borohydride, hydrogenation over Adams catalyst, and reduction by tributyltin hydride have also been reported on occasion. Reductive cyclization by LiAlH4, which is now the method of choice, proceeds... 

A number of nickel(O) catalysts have been synthesized since the initial report of Arduengo et al. containing nickel and palladium NHC catalysts [10]. The work of Matsubara et al. [11] shows the ability to access similar nickel(O) and nickel(II) catalysts from commercially available Ni(acac)2 (Figure 13.2). This synthetic route, which employs sodium hydride to reduce Ni(II) to Ni(0), circumvents the need to use air-sensitive and flammable Ni(COD)2. One other catalyst of note is the 18 e complex synthesized by Spicer and coworkers [12]. The unique structure of the tetradentate NHC ligand serves to stabilize the catalyst as well as facilitate the reduction of several organic structural motifs. 

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