d-(-)-Erythrose has the formula HOCH2¬CH(OH)¬CH(OH)¬CHO, and the d in its name implies that it can be degraded to d-(+)-glyceraldehyde. The (-) in its name implies that d-(-)-erythrose is optically active (levorotatory). When d-(-)-erythrose is reduced (using H2 and a nickel catalyst), it gives an optically inactive product of formula HOCH2¬CH(OH)¬CH(OH)¬CH2OH. Knowing the absolute configuration of d-(+)-glyceraldehyde (Section 5-14), determine the absolute configuration of d-(-)-erythrose.

d-(-)-Erythrose has the formula HOCH2¬CH(OH)¬CH(OH)¬CHO, and the d in its name implies that it can be degraded to d-(+)-glyceraldehyde. The (-) in its name implies that d-(-)-erythrose is optically active (levorotatory). When d-(-)-erythrose is reduced (using H2 and a nickel catalyst), it gives an optically inactive product of formula HOCH2¬CH(OH)¬CH(OH)¬CH2OH. Knowing the absolute configuration of d-(+)-glyceraldehyde (Section 5-14), determine the absolute configuration of d-(-)-erythrose.

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

Chapter25: Carbohydrates

Section: Chapter Questions

Problem 25.15P

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