Transcript Anathons in Developing and Solving Ozonolysis Problems Ray A. Gross, Jr.

Anathons in Developing and
Solving Ozonolysis
Problems
Ray A. Gross, Jr.
40th MARM ACS
Queensborough Community College
Bayside, New York
May 18, 2008
Outline
• Structure-determination problems
• Ozonolysis of hydrocarbons
• Single solution, exclusive of
stereochemistry
• Talk about an approach to solving
the problems, and how they were
developed
Ozonolysis of Alkene
O
H
CH3
C C
H
O
O
H C C CH3
H
H
O3
H
addition
O O
H C
C CH3
H
O H
O O
H C
C CH3
H
O H
rearrangement
Ag2O
O=C=O
O
+ HOCCH3
O
O
(O)
(CH3)2S
(R)
H
C
H
+
HCCH3
Problem 1
HC
O3
CH2O +
(R)
C2H4O
O
O
Step 1
+
C
C
(structures) H
H
CH3
H
Step 2
(anathons)
Step 3
(join)
H
C
H
H
H
H
C C
H
CH3
C
CH3
Ozonolysis of Alkyne
O
(O)
HC CCH3
O=C=O +
O
(R)
HCOH
HOCCH3
O
+ HOCCH3
Problem 2
X
O3
(R)
CH2O2 +
C2H4O2
O
O
Step 1
+
C
C
(structures) H
CH3
OH HO
Step 2
(anathons)
Step 3
(join)
H C
C CH3
H C CCH3
Problem 3
O3
C3H6
(O)
=1
Step 1
(R structures)
Step 2
(anathons)
CO2 +
O
H
O
+
C
H
H
C
H
CH3
H
C
H
Step 3
(join)
C2H4O2
C
CH3
H2C CHCH3
Problem 4
(O)
C2H4O2 + C2H4O2 + C3H4O3
(R)
C2H4O + C2H4O2 + C3H4O3
HC
=1
C O + O C C OH + HO C CH3
H
Step 2
(anathons)
CH3
CH3CH
C C
CH3
Step 3
(join)
O
O
H3C
Step 1
(R structures)
=2
=1
CH3CH CC CCH3
CH3
C CH3
One-Carbon Anathons
(R)
(O)
H2C
CH2O
CO2
HC
CH2O2
CO2
CO2
CO2
C
Anathons are terminal or interior.
Interior anathons may be cyclic or acyclic derived.
Two-Carbon Terminal Anathons
(R)
(O)
CH3CH
C2H4O
C2H4O2
CH3C
C2H4O2
C2H4O2
Three-Carbon Terminal Anathons
(R)
(O)
CH3CH2CH
C3H6O
C3H6O2
(CH3)2C
C3H6O
C3H6O
CH3CH2C
C3H6O2
C3H6O2
C3H4O
C3H4O
Interior Anathons
CHCH
(R)
C2H2O2
(O)
C2H2O4
CHC
C2H2O3
C2H2O4
CC
C2H2O4
C2H2O4
CHCH2CH
C3H4O2
C3H4O4
CCH
C3H4O2
C3H4O3
C3H2O2
C3H2O2
CH3
Join Anathons to make Unknowns
H2C
CH3CH
CH3CH2CH
CH3C
C
CHCH
CHC
CHCH2CH3
C(CH3)3
CCH2CH3
CC
CH
CCH
C
CH3
CH3CH2C
CH3
CHCH2CH
CH
Conclusions
•
•
•
•
Over 300 compounds developed
Helped students improve reasoning
Chemistry limited to ozonolysis
Complement synthesis and
spectroscopy problems
Thinking is permitted!