An optically active D-aldopentose (A) produced an optically inactive alditol (B) upon treatment with H2/Pt. When the aldopentose (A) was subjected to a Ruff degradation, D-aldotetrose (C) was generated. The aldotetrose (C) gave an optically active aldaric acid (D) upon oxidation with HNO3. D-aldopentose (A) can be prepared from D-threose by a Killani Fischer synthesis. Propose structure of A through D.

An optically active D-aldopentose (A) produced an optically inactive alditol (B) upon treatment with H2/Pt. When the aldopentose (A) was subjected to a Ruff degradation, D-aldotetrose (C) was generated. The aldotetrose (C) gave an optically active aldaric acid (D) upon oxidation with HNO3. D-aldopentose (A) can be prepared from D-threose by a Killani Fischer synthesis. Propose structure of A through D.

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

Chapter10: Alcohols

Section: Chapter Questions

Problem 10.59P

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