Final Exam for Organic I - Rutgers Universitycrab.rutgers.edu/~alroche/fall09org1final.pdfFall 09...
Transcript of Final Exam for Organic I - Rutgers Universitycrab.rutgers.edu/~alroche/fall09org1final.pdfFall 09...
Fall 09 Organic I Final Exam 200pts (graded as 300pts) Name If you do not want your graded exam placed in the box outside my office, then please tick here 1) (10pts) Give one definition of an Acid b) Without using profanity, what is “Organic Chemistry”? c) What is the difference between structural isomers and stereoisomers? d) Provide an example of each type of the above isomers. 2) Briefly explain what is meant the following terms:(16pts) Electronegativity Chiral Molecule Concerted Process Rate Determining Step Syn Addition Markovnikov Addition Mechanism π Bond
Fall09-org1final Page 1
3) Name the classes of compound that the following molecules belong to (E.g. alkane,
amide, etc). (15pts)
R O-HR O-R
O
RR
O
HR
O
O-HR
O
O-RR
R O-O-R
O
O-O-HR
R S-H
R R
4) (16pts) For the below molecule, calculate the number of…
HN
OO CH3
a) carbon atoms b) hydrogen atoms c) oxygen atoms d) π bonds e) sp2 hybridized carbons f) sp2 hybridized atoms g) sp3 hybridized atoms h) lone pairs (non bonding pairs) of electrons
Fall09-org1final Page 2
5) (4pts) What is meant by the term Hydrocarbon ?
(ii) What is a free radical ? 6) (12pts): For the below energy level diagram…
a) is this reaction exothermic or endothermic ? b) Will the Equilibrium constant (K) be greater or less than 1.00 ? c) how many transition states are there ? d) how many steps is this multistep reaction ? e) which step is the rate determining step ? f) which is the fastest step ?
Fall09-org1final Page 3
7) Explain (including curly arrows) why in this electrophilic addition reaction, none of product A is generated, and product B is formed exclusively. (8pts)
H
H
CH3
CH3
H-ClH
H
H
CH3CH3
Cl
H-ClCH3
CH3
H
HH
Cl
Product BProduct A
X
Fall09-org1final Page 4
8) Name the following molecules in IUPAC form. (16pts)
(c)
(d)
(b)
(a)
(e)
Br
OH
I
F
F
Cl
Fall09-org1final Page 5
9) Asterix (star, *) the chiral atoms in these molecules, and assign R or S to each chiral center. (13pts)
(c)
(d)
(b)
(a)F
CH3FCl
CF2HHClHCl
CF2H
H
Cl
Cl
CF3
BrBr
H
H
10) Which of the above molecules are achiral, and in a sentence explain what makes
em achiral. (3pts)
th
Fall09-org1final Page 6
11) Circle the more stable member of each pair, and in a sentence explain your choice. (10pts)
(a)
(b)
(c)
(d) CH2
(e)
CH3CH2O CFH2CH2O__
H2NHO_ _
+ +
++
__
12) Circle the most stable member of each threesome (12pts)
(a)
(b)
(c)
OH
OH
F
H
BrCl
Cl
H
BrF
OH
Br
H
FCl
(d) Br
CH3
BrBr
CH3
Br
H H
Br
HHBr
HH
Br
HHH
H BrBr
HH
CH3
Fall09-org1final Page 7
13) Provide a mechanistic explanation for the observed mixture of products in the following E1 reaction. (10pts)
NaOCH3
E1
H3CCH3
BrH3C
CH3
CH3
H3CCH3
CH3CH3
H3CCH3
CH2
14) How many axial positions are occupied by Hydrogen atoms in the lowest energy onformation of the below molecule? (5pts)
c
Br Br
Fall09-org1final Page 8
15) Give the products of 5 of the 6 following reactions. (15pts)
(c)
(d)
(b)
(a)
(e)
CH3CH3CH2
I
excess I2
1) Mg, Ether
2) H2C=O3) H3O+
1) BH3.THF
2) H2O2, NaOHH3C H
HH3C
(f) PhPh1) Na, NH3
Br2
OsO4, H2O2
15b) Write the mechanism for one of the preceding reactions. (10pts)
Fall09-org1final Page 9
16) Give reagents to perform 5 of the 6 following transformations. (15pts)
(c)
(d)
(b)
(a)
(e)
OH
HH3C
(f) HH3C
OH O
HCH3CH2
O
OH
CH3
O
OCH3
H
H
Br
16b) Write the mechanism for one of the preceding reactions. (10pts)
Fall09-org1final Page 10