At 100 °C, d-idose exists mostly (about 86%) as a 1,6-anhydropyranose:

(a) Draw the chair conformation of this compound.

(b) Explain why d-idose has more of the anhydro form than d-glucose. (Under the same conditions, glucose contains only 0.2% of the 1,6-anhydro form.)

Transcribed Image Text:

НО Н- НО Н- CH -Н -ОН -Н -O-CH2 1,6-anhydro-D-idopyranose