Di-isobutylaluminium hydride

Di-isobutylaluminium hydride reduction33 of aldehyde-derived O-TBDMS cyanohydrins, followed by hydrolysis with a tartaric acid buffer, gives the corresponding O-protected 2-hydroxyaldehydes. Related methodology has been employed in a diastereo-selective synthesis34 of a potential precursor of taxol . 

The condensation of 1,2-diamino-4-nitrobenzene with bornane-2,3-dione has been investigated.290 Catalytic hydrogenation of fenchone oxime (203 X = NOH) gives the imine (203 X = NH) exclusively, whereas camphor oxime gives only the exo-amine (204) reduction with di-isobutylaluminium hydride yields predominantly heterocyclic secondary amines thus (203 X = NOH) gives (205) as the major product together with (206) and (204) and its endo-isomer.291... 

Dibal denotes di-isobutylaluminium hydride. h RN denotes retention IN denotes inversion. 

Reduction of the succinimide (140) with di-isobutylaluminium hydride gives a mixture of diastereoisomers (141), treatment of which (with formic acid) gives the c/s-decalin (142) stereospecifically (Scheme 58). 

New routes to bases of the emetine type have been developed. In one, ( )-protoemetine (118) has been prepared by the reduction of the jS-hydroxy-nitrile (117) with lithium di-isobutylaluminium hydride, (117) being obtained from the known ketone (116) by a Reformatsky-type reaction. 

A valuable method for the synthesis of isomerically pure a/5-unsaturated nitriles via the hydroalumination of alkynes has been reported by Zweifel, Snow and Whitney [107]. Addition of di-isobutylaluminium hydride to an alkyne gives the trans-vinylalane (33) in 90% yield. Compound (33) does not react with cyanogen at room temperature but gives the vinylalanate (34) with methyl lithium. The latter reacts with cyanogen to given the trans-a,i3-unsaturated nitrile. 

Reduction of the cyano function of (434) to aldehyde proceeds in very high yield on employing di-isobutylaluminium hydride. Acid-catalysed cleavage of (435) (Bn = benzyl) leads only to the trans-diaminocyclopropane (436) and not to the... 

The racemic anhydro-sugar (177) (obtained by epoxidation of parasorbic acid) has been converted into DL-desosamine (178) by ring-opening with aqueous di-methylamine, lactonization of the resulting 3-dimethylaminohexonic acid, and reduction of the lactone obtained with di-isobutylaluminium hydride. ... 

L-tyvelose). Acid-catalysed ring-opening of the racemic epoxide (177) in refluxing methanol and reduction of the product with di-isobutylaluminium hydride gave DL-chalcose (296). ... 

Di-isobutylaluminium hydride (DIBAL) reduces acid imidazolides to aldehydes in high yields this method has been successfully applied to the synthesis of a-amino-aldehydes from a-amino-acids/ Similarly the acid thiazolidine derivatives (11), which are also readily obtained from carboxylic acids, are reduced by either DIBAL or lithium tri-t-butoxyaluminium hydride to the corresponding aldehyde." ... 

Vinylaluminiums, prepared from addition of di-isobutylaluminium hydride to acetylenes, are converted by addition of methyl-lithium into the corresponding... 

The conversion of lactones to thionolactones using trimethyloxonium tetrafluoroborate followed by sodium hydrosulphide has been described by Kaloustian and Khouri. Five-, six-, and seven-membered thionolactones are formed in 44—90% yield, but thioester by-products were also formed in some cases. Ethers are formed from lactones by reaction with di-isobutylaluminium hydride followed by triethylsilane and Bp3-OEt2 yields in the range 50—88% are achieved. 

Treatment of t-butyl(phenyl)acetylene with di-isobutylaluminium hydride under various conditions has been studied. The products are (166) and (167)... 

Di-isobutylaluminium hydride induces the reductive rearrangement of enol acetates to 2,4-diols (Scheme 143), a transformation related to the known reductive rearrangement of enol lactones. 

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