441.

Ziegler Method (Thorpe-Ziegler Method)

K. Ziegler et al., Ann. 504, 94 (1933).

Cyclization of dinitriles at high dilution in dialkyl ether in the presence of ether-soluble metal alkylanilide and hydrolysis of the resultant imino-nitrile with formation of macrocyclic ketones (yield is dependent on ring size):

K. Ziegler et al., ibid. 511, 1 (1933) 512, 164; 513, 43 (1934); idem, Ber. 67, 139 (1934); idem, et al., Ann. 528, 114, 143 (1937); R. C. Fuson in Organic Chemistry vol. I, H. Gilman, Ed. (New York, 1943) p 89; V. Migrdichian, The Chemistry of Organic Cyanogen Compounds (New York, 1947) p 288; K. Ziegler, Houben-Weyl 4/2, 758 (1955). Review: J. P. Schaefer, J. J. Bloomfield, Org. React. 15, 1-203 (1967). Cf. Thorpe Reaction.