Butyllithium - lithium

Most applications of this derivative have been for the preparation and modification of amino acids, although some applications in the area of carbohydrates have been reported. The derivative is stable to -butyllithium, lithium diiso-propylamide, and t-BuOK. ... 

Bromopene Propane, 2-bromo- (8) 1-Propene, 2-bromo- (9) (557-93-7) tert-Butyllithium Lithium, tert-butyl- (8) Lithium, (1,1-dimethylethy )- (19) (594-19-4)... 

Lithium ethoxide Ethyl alcohol, lithium salt (8) Ethanol, lithium salt (9) (2388-07-0) sec-Butyllithium Lithium, sec-butyl- (8) Lithium, (1-methylpropyl)- (9) (598-30-1) Acetyl chloride (8,9) (75-36-5)... 

Bromo-9-phenylfluorene 9H-Fluorene, 9-bromo-9-phenyl- (9) (55135-66-5) Butyllithium, lithium, butyl- (8,9) (109-72-8)... 

Styrene, benzene, and tetrahydrofuran were purified as described previously (8,11). Solutions of ec-butyllithium (Lithium Corporation of America, 12.0 wt % in cyclohexane) and methyllithium (Alfa, 1.45 M in ether) and lithium naphthalene were analyzed using the double titration procedure with 1,2-dibromoethane (12). Lithium naphthalene was prepared in tetrahydrofuran from lithium metal and a 25 mole % excess of sublimed naphthalene at -25°C using standard high vacuum procedures. Sealed ampoules of lithium naphthalene were stored in liquid nitrogen. 

Thus, starting from the (—)-(S )-a-(methoxymethyl)benzeneethanaminc derived imines at low temperatures, (S )-2-methylcycloalkanones are obtained via the -azaenolates, whereas (R)-configurated products are obtained via the thermodynamically more stable Z-azaenolates by refluxing the anion solutions prior to alkylation. However, a high degree of enantiomeric excess is obtained only under thermodynamic conditions, presumably due to different selectives in the alkylation step (see Table 3). Variation of the base (/ert-butyllithium, lithium diethylamide, lithium 2,2,6,6-tetramethylpiperidide) and additives (hexamethylphosphoric triamide) did not improve the EjZ ratio (enantiomeric excess) significantly9. 

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