Sugasawa synthesis

INDOLES FROM ANILINES via o-CHLOROACETYLATION-THE SUGASAWA SYNTHESIS... 

It is possible to directly chloroacylate an aniline using chloroacetonitrile and boron trifluoride, ortho to the nitrogen. After (V-acylation, ring closure produces iV-acetyl-indoxyls. The Sugasawa synthesis of indoles utilises these same orf/to-chloroacetyl-anilines, via borohydride reduction and ring closure. ... 

From ortho-chloroacetyl arylamines Sugasawa synthesis... 

Reference may also be made to the synthesis of various alkylated laudanosolines by Schopf, Jackh and Perrey, e.g., laudanosoline 6 7 3 -tribenzyl-4 -methyl ether and laudanosoline 4 -methyl ether, to the preparation of the 3 7-dimethyl ether by Schopf and Thierfelder (1939), and to Robinson and Sugasawa s synthesis of proiosinomenine (4 7-dimethyl ether of laudanosoline). 

Sugasawa Toyoda Adachi Sasakura J Am. Chem. Soc. 1978,100. 4842 Nagala Okada Aoki Synthesis 1979, 365. 

Yamato Sugasawa Tetrahedron Leu. 1970, 4383 Appel Klcinstuck Ziehn Chem. Ber. 1971, 104. 1030 Harrison Hodge Rogers Synthesis 1977, 41. 

A third synthesis of XX, by Sugasawa and Yoshikawa (13), begins with a normal Pictet-Spengler condensation using cyclohexane-1,2-... 

Sugasawa, T., Adachi, M., Sasakura, K., Kitagawa, A. Aminohaloborane in organic synthesis. 2. Simple synthesis of indoles and 1-acyl-3-indolinones using specific ortho a-chloroacetylation of anilines. J. Org. Chem. 1979,44, 578-586. 

Sugasawa et al.u in a series of model studies directed toward the total synthesis of camptothecin, allowed 2-pyrrolidinone (53) to react with diketene (54) followed by ammonium acetate in acetic acid to afford 2-methyl-4,6,7,8-tetrahydropyrrolo[l,2-a]pyrimidin-4-one (56). Presumably, keto imide 55 is an intermediate in this reaction [Eq. (15)]. 

Chemical, synthetic, and clinical studies concerned with camptothecin have been reviewed " another review deals just with the nine total syntheses so far published. Full details of Sugasawa s synthesis have been given. ... 

Kikukawa, N., Takemori, M., Nagano, Y., Sugasawa, M., Kobayashi, S. Synthesis and magnetic properties of nanostructured spinel ferrites using a glycine-nitrate process. J. Magn. 

Nucleophilic cyclization is a common tactic in all branches of organic chemistry, and several indole ring syntheses, which are presented in Chapters 8 through 22, employ this reaction as the central theme in the synthesis. The Sugasawa indole synthesis (Chapter 22) uses both nucleophilic and electrophilic reactions. 

The Sugasawa modification has been effectively used in the synthesis... 

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