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Sodium hydride is the chemical compound with the empirical formula Na H.This alkali metal hydride is primarily used as a strong yet combustible base in organic synthesis.NaH is a saline (salt-like) hydride, composed of Na + and H − ions, in contrast to molecular hydrides such as borane, silane, germane, ammonia, and methane.
The alkylphosphonium salt is deprotonated with a strong base such as n-butyllithium: [Ph 3 P + CH 2 R]X − + C 4 H 9 Li → Ph 3 P=CHR + LiX + C 4 H 10. Besides n-butyllithium (n BuLi), other strong bases like sodium and potassium t-butoxide (t BuONa, t BuOK), lithium, sodium and potassium hexamethyldisilazide (LiHMDS, NaHMDS, KHDMS, where HDMS = N(SiMe 3) 2), or sodium hydride (NaH) are also ...
Metal hydrides (sodium hydride, lithium aluminium hydride, uranium trihydride) Partially or fully alkylated derivatives of metal and nonmetal hydrides (diethylaluminium hydride, trimethylaluminium, triethylaluminium, butyllithium), with a few exceptions (i.e. dimethylmercury and tetraethyllead) Copper fuel cell catalysts (zinc oxide, aluminium ...
Reductive desulfonylation is typically accomplished with active metals or salts (sodium amalgam, aluminium amalgam, magnesium, samarium(II) iodide), tin hydrides (tributyltin hydride), or transition metal complexes with reducing agents or nucleophiles (PdCl 2 (dppp)/LiHBEt 3, Pd(PPh 3) 4 /LiHBEt 3, Pd(PPh 3) 4 /NaHC(CO 2 Et) 2). Alkyl, alkenyl ...
Since many substrates are not stable to sodium hydride, several procedures have been developed using milder bases. Masamune and Roush have developed mild conditions using lithium chloride and DBU. [18] Rathke extended this to lithium or magnesium halides with triethylamine. [19]
Sodium borohydride and lithium aluminium hydride are commonly used for the reduction of organic compounds. [3] [4] These two reagents are on the extremes of reactivity—whereas lithium aluminium hydride reacts with nearly all reducible functional groups, sodium borohydride reacts with a much more limited range of functional groups. Diminished ...
Dowd–Beckwith ring expansion reaction mechanism. The reaction mechanism involves a bicyclic intermediate. The reaction is initiated by thermal decomposition of AIBN.The resulting radicals abstract hydrogen from tributyltin hydride to a tributyltin radical which in turn abstracts the halogen atom to form an alkyl radical.
If an alkoxide such as sodium ethoxide is used as base, deprotonation takes place only to the extent of about 0.1% because acetone is a weaker acid than ethanol (pK a = 16). If, however, a more powerful base such as sodium hydride (NaH) or lithium diisopropylamide ( LDA ) is used, a carbonyl compound can be completely converted into its enolate ...