Synthesis Sorensen method

The Sorensen method of amino acid synthesis uses a modification of the malonic ester synthesis. In this modification an N-protected malonic ester is alkylated, hydrolyzed and decarboxylated to give an a-amino acid, as shown in equation 77. 

Other examples of the reaction are the cyanoacetic ester synthesis, in which Z is COOEt and Z is CN (as in the malonic ester synthesis, the product here can be hydrolyzed and decarboxylated), and the Sorensen method of amino acid synthesis, in which... 

K. C. Nicolaou and E. J. Sorensen, in Classics in Total Synthesis, Targets, Strategies, and Methods, VCH, Weinheim, 1996. 

The development of the chemistry of organometallic compounds containing the pentamethylcyclopentadienyl ligand has been hampered by the lack of a simple, high yield synthesis of 1,2,3,4,5-pentamethylcyclopentadiene (14). We have recently expanded the method first reported by Sorensen et al. (15) to a large scale preparation which follows Scheme 1 (16). This procedure is applicable... 

The classical method of BCMO synthesis is by Sorensen and Campbell9) ... 

Nicolaou, K. C., and Sorensen, E. J. (1996). Classics in Total Synthesis Targets, Strategies, Methods. Weinheim, NY VHE. 

Nicolaou, K.C., Sorensen, E.J. Classics in total synthesis targets, strategies methods. Wiley, New York (1996)... 

Synthesis. Schulse and Winterstein (706, 708) prepared 1 g. of arginine nitrate by allowing a solution of cyanamide and ornithine to evaporate over sulfuric acid for three weeks while Sorensen et al. (747, 750) synthesized arginine nitrate by the reaction of cyanamide and a-benzoylamino-S-amino-n-valeric acid. Ornithine is readily synthesized from cyclopentanone by the methods described by Fox et al. (328) and Albertson and Archer (47) and ornithuric acid ( , -dibenzoylamino-n-valeric acid) is easily prepared by the benzoylation of ornithine. The other steps in the described syntheses of arginine are less satisfactory since they involve either tiie selective reaction of cyanamide with the 8-amino group of ornithine or the selective hydrolysis of the 8-benzoyl group of ornithuric acid. 

Nicolau KC, Sorensen EJ. Classics in total synthesis. Targets, strategies, methods. Weinheim Wiley-VCH 1996. 

Stoeva, S., K. J. Klabunde, C. M. Sorensen, and I. Dragieva. 2002. Gram-scale synthesis of monodisperse gold colloids by the solvated metal atom dispersion method and digestive ripening and their organization into two- and three-dimensional structures. J. Am. Chem. Soc. 124 (10) 2305-2311. 

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