I ~ c...,h. 0\ 'c.. -c_.:--c_-1. ena.. "'~" /1 ~ 04 IJ; \ ~ CHEM 241 EXAM #1A (100 points) /\\ o... ll. lr'- 1 c:::;:::c H / ',,,,H

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1 CEM 241 EXAM #1A (100 points) Fall 2015 s~yii\ J.o~.cv. ~rn '5 ~ 1. (8 pts 4 pts each) Draw the condensed or line formula for: ena.. Trans-1-chloro-2-pentane 2,5- dibromo-2-heptanol 2. (15 pts, 5 pts ea) Give the IUP AC name for the structures shown below: Cl 3. a) (3 pts) In the structure below, circle the atoms that are sp hybridized b) (3 pts) Draw an arrow ( 7) to any bonds that contain a pi ( 1t) bond. c) (6 pts) Some of the geometry is incorrect Draw the molecule correctly using the proper geometry for all the atoms. /\\ o... ll 0\ 'c.. -c_.:--c_-1,,,"(>. / - \.. "'~" /1 ~ 04 / -C. " u IJ; \ ~ lr'- 1 c:::;:::c / ',,,, c..., I ~

2 4. a. (8 pts) Assign formal charges to all the atoms in the molecules shown below (all lone pair electrons are shown): el \ I : N: 'c/ c-c ~' - \ / \ o: e o:~ C-C- / II I,...c,. \ &> N- 5. a. (6 pts) Draw the other chair conformation for the substituted cyclohexane shown below b. (2 pts) circle the conformation that is the most stable (lowest energy). Circle neither if they are equal in energy. / \ 6. a (3 pts) Circle the perspective formula(s) below that you would consider being 'fully staggered'-where all C-C bonds are in the staggered conformation. b. (6 pts) From the molecules below draw an arrow (7) to any C-C bonds that are eclipsed. ~--. I \ C \. ~',::- ~'. /c,. /c.,,,,, ':-c/ 'c/ \ '''/ ~::,_ l - - ;,, / a... ~ ~ ~c ~c-c ~'7c---c. 1 I \ I \!~ /c, /c, ;., II~C/ "-c/ "-c '''' I ~::.. I

3 (4 pts) Write ad+ or D- by the appropriate atoms. Electronegativity values: -2.1 C-2.5 N-3.0 Cl A conformation of 2-butanol is drawn below. 5- o s-... c, c1' ~ 'o"'. 5- N==N II ~t a) (4 pts) Rotate about the Carbon--Carbon bond to any conformation that is lowest in energy (draw this conformation using the dash wedge perspective formula.). b) (4 pts) Next to your drawing from 8a draw the corresponding Newman projection of the lowest energy conformation C3 \ / rotate,,,,,,,,,.. c--c\..,,, c.o O ~ " C3 'lowest energy' Newman projection 9 a. (3 pts) Circle the tribromocyclohexane below that would have a chair conformation in which a113 bromo groups would be in the equatorial position. ooiiii b. (5 pts) For the compound your circled above, draw the chair conformation showing all 3 bromo groups equatorial.

4 10. Answer a-e for the methyl cyclohexanol structures A- below. C 3~ ::::['C3 ~O C3~ D O A B O C _p ' ~ 3-z:::::r h C C,IIIU O E C3 F G a. (4 pts) What is the relationship ofc and D? Circle one: O O O ~ I,LJ \IS 1,3 a) Identical b) different conformations c) Geometric isomer~nstitutional isomers b. (4 pts) What is the relationship of A and? Circle one: a~,,'j...t,...,~ a) Identical@ifferent conformations c) Geometric isomers d) constitutional isomers c. (4 pts) Which structures(s) would be considered 'trans' 3-methyl-1-cyclohexanol? ~~ d (4 pts) Which structure(s) are Geometric/Stereo isomers of,.? B ~ s l1z.. Tr4h$1 1 J.. e. (4 pts) Which structure(s) would you consider to be a chair conformation ofe? #-- P Extra credit 1. (5 pts) The line structure of the famous glucose molecule is shown below. There are many possible cis/trans isomer possibilities for glucose that nature could produce but it produces only one-the lowest energy form. Depict the lower energy form using dash wedge notation as well as the lowest energy chair conformation. ~ ~1l.~-~ju'it,n 1 / O YO'YO ovo O Glucose 2. Name the molecules below (5 pts) Dash-wedge (Ji. 1-10~:0. ~ ~~ Chair conformation ~ Oy F (A cube of carbons)

5 CEM 241 EXAM #1B (100 points) Fall (15 pts, 5 pts ea) Give the IUP AC name for the structures shown below: C3C2C2CC2C2C2C3 I C 2 C 3 Name O 6 2. (8 pts 4 pts each) Draw the condensed or line formula for: ~ M.~.t lw\"\.h z S"-'d\.\\c,l b.,... <:- eh l,y,.. 2-f DJfb\.)./ cis-1-chloro-3-pent~ c,. 2,6- dibromo-2-hexanol 3. a) (3 pts) In the structure below, circle the atoms that are sp hybridized b) (3 pts) Draw an arrow ( 7) to any bonds that contain a pi ( 1t) bond. c) (6 pts) Some of the geometry is incorrect Draw the molecule correctly using the proper geometry for all the atoms.

6 4. a. ( 6 pts) Draw the other chair conformation for the substituted cyclohexane shown below b. (2 pts) circle the conformation that is the most stable (lowest energy). Circle neither if they are equal in energy. 5. a. (8 pts) Assign formal charges to all the atoms in the molecules shown below (all lone pair electrons are shown):. 6. a (3 pts) Circle the perspective formula(s) below that you would consider being 'fully staggered'-where all C-C bonds are in the staggered conformation. b. (6 pts) From the molecules below draw an arrow (-7) to any C-C bonds that are eclipsed. \ I ~',::-. /c, /c,.. ;, II~C/ "'-c/ "'-c '''' I ~==- I \ ~-- C ~' I /c, /c..,,,, "-c/ "'-c/ \,~~ j~ ~. 4-

7 7. (4 pts) Write a 8 +or 8- by the appropriate atoms. Electronegativity values: -2.1 C-2.5 N-3.0 Cl A conformation of 2-butanol is drawn below. ~- 0 N:=N II ~;-.s-ci /I-t'-...0/ s- a) (4 pts) Rotate about the Carbon--Carbon bond to any conformation that is lowest in energy (draw this conformation using the dash wedge perspective formula.). b) (4 pts) Next to your drawing from 8a draw the corresponding Newman projection of the lowest energy conformation rotate 'lowest energy' Newman projection 9 a. (3 pts) Circle the tribromocyclohexane below that would have a chair conformation in which all3 bromo groups would be in the axial position. lllll "".,,.,II b. (5 pts) For the compound your circled above, draw the chair conformation showing all3 bromo groups axial. 13r

8 ~- --~-----~ Answer a-e for the methyl cyclohexanol structures A- below. c,-c/ C:::{c, b::to A B O C C3~ D O O y=:\ C3 F C,-z::::.; E O a. (4 pts) What is the relationship ofe and? Circle one: G h O 1~,.,1',... ~,, 'V a) Identica'C'"ifferent conformations c) Geometric isomers d) constitutional isomers b. (4 pts) What is the relationship ofc and D? Circle one: 1.4fS l,'! a) Identical b) different conformations c) Geometric isomer~onstitutional isomers c. (4 pts) Which structures(s) would be considered 'trans' 4-methyl-1-cyclohexanol? F ---- d ( 4 pts) Which structure( s) would you consider to be a chair conformation of A?--=.,J2. C1s \ 1 l 1'~ e. (4 pts) Which structure(s) are Geometric/Stereo isomers of?---'s""'----- Extra credit tn.., 1,1- "S Cts 1, (5 pts) The line structure of the famous glucose molecule is shown below. There are many possible cis/trans isomer possibilities for glucose that nature could produce but it produces only one-the lowest energy form. Depict the lower energy form using dash wedge notation as well as the lowest energy chair conformation. O O Glucose 2. Name the molecules below (5 pts) 5() Oy F Dash-wedge Chair conformation (A cube of carbons)