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Two pictures of the same thing.
Write a curved arrow mechanism and predict the product. Submit a picture
This is pretty complicated for OscerSketch
You might want to do it on paper.
OH
OH
HO
OH
OH
1
O
5 4 3
6
2
O
HO
OH
O
Cyclic hemiacetal
Cyclic hemiacetal
Which two products are possible?
OH
OH
Which one of the two is favored?
OH
A i + ii B i + iii C i + iv D ii + iii E ii + iv F iii + iv
OH
O
i
OH
6
4
5
O
3 2 1
O
OH
ii OH
OH
H
HO
O
OH
HO
OH
O
HO
2
3
4
iii iv
1
O
4
OH
6
D or L
instead of
R or S HO
HO
O
OH
OH
D‐glucose
OH
These
3 chiral
centers
Give 8 D‐aldohexoses
D‐Allose
D‐Glucose
D‐Gulose
D‐Galactose
D‐Altrose
D‐Mannose
D‐Idose
D‐Talose
16 aldohexoses including the corresponding L‐isomers
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an Aldopentose
This is a generic representation of an aldopentose, a five carbon sugar
an Aldopentose
This is a generic representation of an aldopentose, a five carbon sugar
How many aldopentose diastereomers can exist? A 2 B 4 C 8 D 16
an Aldopentose
This is a generic representation of an aldopentose, a five carbon sugar
How many aldopentose diastereomers can exist? an Aldopentose
This is a generic representation of an aldopentose, a five carbon sugar
How many aldopentose diastereomers can exist? 2
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an Aldopentose
an Alditol
an Aldopentose
an Alditol
If you treat an aldehyde with sodium borohydride in water you reduce it to an alcohol.
If you treat an aldehyde with sodium borohydride in water you reduce it to an alcohol.
A reduced aldopentose is called a alditol. A reduced aldopentose is called a alditol. How many 5 carbon alditol diastereomers can exist? Draw them and label the chirality centers
If you treat an aldehyde with sodium borohydride in water you reduce it to an alcohol.
A reduced aldopentose is called a alditol. How many 5 carbon alditol diastereomers can exist? How many 5 carbon alditol diastereomers can exist? A 3 B 4 C 5 D 6 E 7 F 8
Draw them and label the chirality centers
A 3 B 4 C 5 D 6 E 7 F 8
Draw them and label the chirality centers
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Predict Product
O
R
R
R
O
OH
O
O
R
R
R
O
OH
O
R
O
R
A B C D
Draw and name the NaBH4
reduction product of D‐Lyxose
H+
O
R
R
HO
OH
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H
O
R
O
H
R
HO
R
O
O
H
O
O
R
R
R
R
R
Cyclic Acetal
R
R
HO
H
R
O
Give a sequence of reaction to carry out
the above transformation
HO
O
H+
O
O
OH
R
H
R
R
H+
H
O
O
R
O
R
H
HO
H
O
O
H
R
HO
R
Hemiacetal
5