ジアゼンジカルボン酸ジ-tert-ブチル

使用Di-tert-butyl azodicarboxylate is a reagent used in the preparation of acyl hydrazinedicarboxylates. It is also used in the electrophilic amination of beta-keto esters catalyzed by an axially chiral guanidine. It serves as a precursor in an enantioselective synthesis of 3,6-dihyropyridazines employing organocatalysts such as L-proline or (S)-2-pyrrolidinyl tetrazole. It is also utilized in the asymmetric Friedel-Crafts amination through a chiral organocatalyst. Further, it acts as a reactant for preparation of hexapeptide key fragments through stereo selective selenocyclization/oxidative deselenylation reactions. In addition to this, it is employed as a starting material in the synthesis of pyrroloisoquinoline template through stereoselective N-acyliminium-mediated cyclization and enolate amination for preparation of peptidomimetic compounds and Barbier-type propargylation reactions.

一般的な説明Di-tert-butyl azodicarboxylate is a an acid labile reagent for Mitsunobu reactions allowing facile isolation of products and for the electrophilic amination and hydrazination of enolates and lithium alkyls.

純化方法The tert-butyl ester has the advantage over the ethyl ester (below) in being a solid and more acid labile. It crystallises from ligroin and is best purified by covering the dry solid (22g) with pet ether (b 30-60o, 35-40 mL) heating to boiling and adding ligroin (b 60-90o) until the solid dissolves. On cooling, large lemon yellow crystals of the ester separate (~ 20g), m 90.7-92o. Evaporation of the filtrate gives a further crop of crystals [Carpino & Crowley Org Synth 44 18 1964]. This reagent is useful in the Mitsunobu reaction [Mitsunobu Synthesis 1 1981, Gennari et al. J Am Chem Soc 108 6394 1986, Evans et al. J Am Chem Soc 108 6394 1986, Hughes Org React 42 335 1992, Dodge et al. Org Synth 73 110 1996, Hughes Org Prep Proc Int 28 127 1996, Ferguson & Marcelle J Am Chem Soc 128 4576 2006, see also DEAD and DIAD below].