Ribose, a carbohydrate with the formula shown, forms a cyclic hemiacetal, which, in principle, could contain either a four-membered, five-membered, or six-membered ring. To determine which ring is formed, ribose is treated with methanol in the presence of an acid catalyst. The products are then isolated and treated with NalO, then with H30*. он MEOH 1. NalO. 2. H,O* A & B MEOH + products HO H* isomeric cyclic acetals with formula CgH1205 ÕH Ribose, CSH1005

Ribose, a carbohydrate with the formula shown, forms a cyclic hemiacetal, which, in principle, could contain either a four-membered, five-membered, or six-membered ring. To determine which ring is formed, ribose is treated with methanol in the presence of an acid catalyst. The products are then isolated and treated with NalO, then with H30. он MEOH 1. NalO. 2. H,O A & B MEOH + products HO H* isomeric cyclic acetals with formula CgH1205 ÕH Ribose, CSH1005

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter16: Aldehydes And Ketones

Section: Chapter Questions

Problem 16.70P

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