Alanes synthesis

Especially in the early steps of the synthesis of a complex molecule, there are plenty of examples in which epoxides are allowed to react with organometallic reagents. In particular, treatment of enantiomerically pure terminal epoxides with alkyl-, alkenyl-, or aryl-Grignard reagents in the presence of catalytic amounts of a copper salt, corresponding cuprates, or metal acetylides via alanate chemistry, provides a general route to optically active substituted alcohols useful as valuable building blocks in complex syntheses. 

Niobium, tris(diethyldilhiocarbamato)oxy-stereochemistry, 1,82 structure, 1, 83 Niobium, tris(oxa ato)oxy-stereochcmistry, 1, 82 Niobium, tris(phcnylcncdirhio)-structure, 1, 63 Niobium alanate, 3, 685 Niobium complexes alkyl alkoxy reactions, 2, 358 amides, 2,164 properties, 2, 168 synthesis, 2, 165 applications, 6,1014 carbamicacid, 2, 450 clusters, 3, 672,673,675 hexamethylbenzene ligands, 3, 669 cyanides synthesis, 2, 9 p-dinitrogen, 3, 418 fluoro... 

The aziridine-2-carboxaldehyde 56 can also serve as synthon for the synthesis of sphingosines, which are important biomembrane constituents [64]. One possible route involves the addition of an alanate to the aldehyde. In a later stage of this synthetic plan the aziridine can be opened, either via the intermediacy of an oxazoline or directly with dilute acid. Unfortunately, the reaction of aldehyde 56 with a vinylalanate has a poor diastereoselectivity of 3 2. Therefore, an alternative approach was considered, namely one involving the addition of a vinylzinc reagent to the aldehyde thereby employing our N-tritylaziridinediphenyl-methanol 51 as the chiral catalyst. Gratifyingly, only one diastereomer was obtained. Reductive removal of the trityl function, acetylation of the hydroxy... 

Sequencing and Synthesis. Selected Methods and Applications Schlesinger, D., Ed. Alan B. Liss Publishers, Ch 19, pp 243-250. 

Scheme 4.10 gives some examples of application of alkyne carboalumination in synthesis. The reaction in Entry 1 was carried out as part of a synthesis of the immunosuppressant drug FK-506. The vinyl alane was subsequently transmetallated to a cuprate reagent (see Chapter 8). In Entry 2, the vinyl alane was used as a nucleophile for opening an epoxide ring and extending the carbon chain by two atoms. In Entries 3 to 5, the vinyl alane adducts were converted to vinyl iodides. In Entry 6, the vinyl alane was converted to an ate reagent prior to reaction with formaldehyde. 

Cowley, Alan H., and Norman, Nicholas C., The Synthesis, Properties, and Reactivities of Stable Compounds Featuring Double Bonding Between... 

Alan G. MacDiarmid Institute, Jilin University, Changchun, 130012, China State Key Lab of Inorganic Synthesis Preparative Chemistry, Jilin University, Changchun, 130012, China... 

R.A. Vatin, Ch. Chiu, T. Czujko, Z. Wronski, Feasibilty study of the direct mechano-chemical synthesis of nanostructured magnesium tetrahydroaluminate (alanate) [Mg(AIH )J complex hydride, Nanotechnology 16 (2005) 2261-2274. 

J.M.B.van Colbe, M. Felderhoff, B. Bogdanovic, F. Schiith, C. Weidenthaler, One-step direct synthesis of a Ti-doped sodium alanate hydrogen storage material , Chem. Commun. (2005) 4732. 

Fichtner et al. [77, 78] added small Ti clusters (Tij3 6THF the synthesis of these clusters is described in [77]) to highly purified NaAlH by ball milling for 30 min and observed a substantial improvement of desorption/absorption kinetics for an alanate doped with 2 mol% of Ti clusters. A doped alanate desorbed on... 

M. Fichtner, O. Fuhr, Synthesis and structures of magnesium alanate and two solvent adducts , J. Alloys Compd. 345 (2002) 286-296. 

M.S.L. Hudson, D. Pukazhselvan, G. Irene Sheeja, O.N. Srivastava, Studies on the synthesis and dehydrogenation behavior of magnesium alanate and magnesium-sodium alanate mixture , Int. J. Hydrogen Energ. 32 (2007) 4933 938. 

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