Triphenylphosphine Copper Hydride

Triphenylphosphine copper hydride hexamer, (HCuPPh3)g, is a highly effective catalyst for the reduction of certain unsaturated hydrocarbons and ketones (12.353,12.354) [36,37]. 

---

ALLYLIC ALCOHOLS Alkyllithium reagents. Bis(triphenylphosphine)-copper(I) tetrahydroborate. r-Butyl-dlmethyliodosilane. Chlorotrimethyl-silane. Cyclohexylisopropylamino-magnesium chloride. Iodotrimethyl-silane. Lithium aluminum hydride-N-Methylephedrine. Lithium 1 -[Pg.240]

The mechanism of reaction of a variety of triphenylphosphinealkyl-gold(i) complexes, and of triphenylphosphinetrimethylgold(iii), with mercury(n) chloride in a variety of solvents is St2. But when the alkyl group is cyano(ethoxycarbonyl)pentyl then the mechanism is dissociative. Decomposition of triphenylphosphine-n-butylcopper must involve initial formation of butene and a transient copper hydride rather than of n-butyl radicals, since no octane can be detected in the ultimate products. ... 

Other Preparations.—Carboxylic acids have been converted into aldehydes through di-isobutylaluminium hydride reduction of 3-acylthiazolidine or 2-thiazoline-2-thiol ester intermediates. Bis(triphenylphosphine)copper(l) tetrahydroborate, (Ph3P)2CuBH4, shows promise as a new reagent for the reduction of acid chlorides to aldehydes. The same conversion can be accomplished using sodium borohydride in a mixture of acetonitrile and hexamethyl-phosphoramide containing a cadmium(il) chloride-dimethylformamide complex. ... 

Lithium wire (3.2 mm diam.), carbon tetrachloride, triphenylphosphine, MgBrEtaO, copper bromide-dimethyl sulfide complex, hexanoyl chloride, methyllithium, p-toluenesulfonic acid monohydrate, potassium hydride, and 18-crown-6 were purchased from Aldrich Chemical Company, Inc. and used without further purification. 

Reduction of acid chlorides to aldehydes One of the most useful synthetic transformations in organic synthesis is the conversion of an acid chloride to the corresponding aldehyde without over-reduction to the alcohol. Until recently, this type of selective reduction was difficult to accomplish and was most frequently effected by catalytic hydrogenation (the Rosenmund reduction section 6.4.1). However, in the past few years, several novel reducing agents have been developed to accomplish the desired transformation. Among the reagents that are available for the partial reduction of acyl chlorides to aldehydes are bis(triphenylphosphine)cuprous borohydride , sodium or lithium tri-terf-butoxyaluminium hydride, complex copper cyanotrihydridoborate salts °, anionic iron carbonyl complexes and tri-n-butyltin hydride in the presence of tetrakis(triphenylphosphine)palladium(0). ... 

Sodium aluminum chloride, 435 Sodium amalgam, 310, 416-417 Sodium amide-Sodium r-butoxide, 417-418 Sodium azide-Triphenylphosphine, 418 Sodium bis(2-methoxyethoxy)aluminum hydride, 166,418-420 Sodium borohydiidc, 323,420-421 Sodium borohydride-Alumina, 421 Sodium borohydride-Bis(2,4-pentane-dionato)copper(ll), 421 Sodium borohydride-Cerium(Ill) chloride,... 

ALKENES Allyl dimethyldithiocarbamate. Bis(t -cyclopentadienyl)niobium trihydride. Cyanogen bromide. Di-n-butylcopperlithium. a,o-Dichloromethyl methyl ether. 2,3-Dimethyl-2-butylborane. N,N-Dimethyl dichlorophosphoramide. Diphenyl diselenide. Di-n-propylcopperlithium. Ferric chloride. Grignard reagents. Iodine. Lithium phenylethynolate. Lithium 2,2,6,6-tetramethylpiperidide. Methyl iodide. o-Nitro-phenyl selenocyanate. Propargyl bromide. rra s-l-Propenyllithium. Selenium. Tetrakis(triphenylphosphine)palladium. Titanium(IH) chloride. Titanium trichloride-Lithium aluminum hydride. p-Toluenesulfonylhydrazine. Triphenylphosphine. Vinyl-copper reagents. Vinyllithium. Zinc. 

The cross-coupling reaction of 226 with a variety of aromatic halides proceeds without difficulty in triethylamine in the presence of bis(triphenylphosphine)palladium(II) chloride and copper(I) iodide under sonication conditions to furnish the corresponding arylacetylenes 229 in satisfactory yields. Refluxing these arylacetylenes with lithium aluminum hydride in THF provides in good yields the corresponding allylic alcohols 230 having the -config-uration [81]. 

---