Protection of Amino Groups tert-Butoxycarbonylation

P Sieber, B Riniker, M Brugger, B Kamber, W Rittel. 255. Human Calcitonin. VI. The synthesis of calcitonin M. (side-chain alkylation) Helv ChimActa 53, 2135,1970. 

LA Carpino, BA Carpino, PJ Crowley, PH Terry. f-Butyl azidoformate. Org Syntheses 15, 1964. 

FIGURE 3.17 Reagents for protection of amino groups as the ferf-butoxycarbonyl derivatives. terf-Butyl chloroformate is rarely used because of its low boiling point. The oxime is 2-ferf-butoxycarbonyloximino-2-phenylacetonitrile,45 Boc20 = di-ferf-butyl dicarbonate, or di-terf-butyl pyrocarbonate.46 (Tarbell et al., 1972 Pozdvev, 1974). Acylations are carried out at pH 9 to avoid dimerization. 

LA Carpino. Oxidative reactions of hydrazines. II. Isophthalimides. New protective groups on nitrogen. J Am Chem Soc 79, 98, 1957. 

FC McKay, NF Albertson. New amine-masking groups for peptide synthesis. J Am Chem Soc 79, 4686, 1957. 

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