Di-t-butyl pyrocarbonate

Procedure for BOC-amino acids. A solution of the amino acid (10 mol) in a mixture of dioxane (20 ml), water (10 ml) and 1 m sodium hydroxide (10 ml) is stirred and cooled in an ice-water bath. Di-t-butyl pyrocarbonate (1) (2.4 g, 11 mmol) is added and stirring is continued at room temperature for 30 minutes. The solution is concentrated in vacuo to about 10-15 ml, cooled in an ice-water bath, covered with a layer of ethyl acetate (30 ml) and acidified with dilute aqueous potassium hydrogen sulphate solution to pH 2-3 (Congo red). The aqueous phase is extracted with ethyl acetate (2 x 15 ml). The ethyl acetate extracts are pooled, washed with water (2 x 30 ml), dried over anhydrous sodium sulphate and evaporated in vacuo. The residue is recrystallised with a suitable solvent (e.g. ethyl acetate-hexane). 

Di-t-butyl dicarbonate CAS 24424-99-5 EINECS/ELINCS 246-240-1 Synonyms t-BOC BOC anhydride Di-t-butyl pyrocarbonate Empirical CioHisOs Formula [CH3)3C0C0]20 Properties M.w. 218.25 m.p. 22-24 C Uses Blocking agent reagent for the introduction of the acid labile BOC protecting group... 

Di-n-butyl phthalate. See Dibutyl phthalate Di-t-butyl pyrocarbonate. See Di-t-butyl dicarbonate Di butyl sebacate... 

Dibutylpropoxyarsine oxide, in D-00226 Di-/er/-butyl pyrocarbonate, in D-00243 0,0-Dibutyl thiophosphite, see D-00240 0,0-Dibutyl thiophosphoric acid, see D-00242 Dicaproylmethane, see T-00228 2,2 -Dicarbamoyldiphenylamine, in 1-00013 Dicarbonic acid, D-00243... 

Di-tert-butyl dicarbonate (or tert-butyl pyrocarbonate) t-Boc20 is an excellent reagent for the preparation of f-Boc-deriv-atives, N-silylmethylamines 128—132 (Table 24.6) (53,79). The stirring of a solution of (phthalimidomethyldimethylsilanyl) alkanols and hydrazine hydrate in absolute ethyl alcohol leads to the formation of aminomethyldimethylsilyl alcohols (53). Their purification on a chromatography column (silica gel) results in numerous degradation products. The protection of their amino groups with di-tert-butyl dicarbonate at room temperature affords more stable t-Boc-derivatives N-silylmethylamines 128-131 (Scheme 24.16). 

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