Sodium trimethoxyborohydride reduction

Complex hydrides can be used for the selective reduction of the carbonyl group although some of them, especially lithium aluminum hydride, may reduce the a, -conjugated double bond as well. Crotonaldehyde was converted to crotyl alcohol by reduction with lithium aluminum hydride [55], magnesium aluminum hydride [577], lithium borohydride [750], sodium boro-hydride [751], sodium trimethoxyborohydride [99], diphenylstarmane [114] and 9-borabicyclo[3,3,l]nonane [764]. A dependable way to convert a, -un-saturated aldehydes to unsaturated alcohols is the Meerwein-Ponndorf reduction [765]. 

Chemical reduction of aromatic aldehydes to alcohols was accomplished with lithium aluminum hydride [5i], alane [770], lithium borohydride [750], sodium borohydride [757], sodium trimethoxyborohydride [99], tetrabutylam-monium borohydride [777], tetrabutylammonium cyanoborohydride [757], B-3-pinanyl-9-borabicyclo[3.3.1]nonane [709], tributylstannane [756], diphenylstan-nane [114], sodium dithionite [262], isopropyl alcohol [755], formaldehyde (crossed Cannizzaro reaction) [i7i] and others. 

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). 

Azines and their Hydro- and Benzo-derivatives Pyridines - Synthesis. Reaction of N - Cbz-5-amino-1-pentene (3) with mercury (II) acetate followed by reduction of the resulting mercuri acetate with sodium trimethoxyborohydride in the presence of methyl acrylate gives the ester (4). This was converted into the tetrahydropyridone (5) by hydrogenolysis followed by warming ... 

In contrast, the mercurial enones (89) (obtained by specific solvomercuration of the corresponding pendant terminal olefins) are isolated, and on treatment with sodium trimethoxyborohydride are reductively cyclized to (90). Alkynes... 

Reactions.—The use of NaBH, in polar aprotic solvents as a convenient and effective source of nucleophilic hydrogen for the reduction of alkyl halides (and tosylates) to alkanes has been reported in full this year. This reagent is selective and does not affect other functional groups such as ester or nitrile (contrast LiAlH4). Sodium trimethoxyborohydride is an alternative, especially for reduction in the presence of alkene functions this report also includes details of a one-pot sequence from alcohols via the iodides to alkanes (Scheme 46). ... 

The reduction of the thiazolium salt, thiamine, has been investigated with sodium borohydride, trimethoxyborohydride, and lithium... 

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