+ HBr ΔH = OH CH CH 2. HgOAc

Transcription

1 radical substitution l hv + l 2 + l Energy radical addition RR + electrophilic addition Energy Energy + 2 acetone water Energy Energy acid catalyzed hydration Energy = 2 2 oxymercuration - reduction (two steps) the first step + g(ac) 2 = Ac Energy Energy Energy hydroboration - oxidation (two steps) gac the first step + B 3 = 2 B 2 2 Energy

2

3 mild ARS cold KMn 4 s cold cis T KMn 4 T KMn 4 1.MPBA 2. +, 2 T KMn 4 trans MPBA meta-chloroperoxybenzoic acid mild MPBA Me 2 S epoxide Know mechanism for epoxidation Zn(s) Me 2 S Know mechanism for epoxide ring opening Synthesis of alkenens acidic condtions 1 Propose a synthesize for cyclohexene from cyclohexane basic condtions 2 Propose a syntheses for compounds 1,2, 3 shown on the right starting from cyclohexane 3 neutral condtions

4 A l k e n e R e a c t i o n s Gi v e l a b e l s, i d e n t i f y c o n d i t i o n s, c o m p l e t e a n d n a m e t h e r e a c t i o n s. o n d i t i o n s ( a c i d i c, b a s i c, n e u t r a l, o x i d i z i n g, r e d u c i n g, p o l a r p r o t i c, p o l a r a p r o t i c, n o n p o l a r, h v e t c. ) reaction name/type l 2 1.B 3 TF , 1.g(Ac) 2, 2 2.NaB 4 l RR hv 4

5 cold KMn 4 reaction name/type hot KMn Zn MPBA l 2 1.MPBA 2. 2, + cold KMn 4 hot KMn 4 5

6 a. Name the reaction and state the reaction. M e c h a n i s m s - A d d i t i o n R e a c t i o n s b. Give a stepwise mechanism for the following reaction. Your mechanism should show individual steps in the reaction that lead to all the products formed. Use curved arrows and indicate all formal charges. reaction name/type reaction name/type 2 + 6

7 M e c h a n i s m s - A d d i t i o n R e a c t i o n s a. Name the reaction and state the reaction. b. Give a stepwise mechanism for the following reaction. Your mechanism should show individual steps in the reaction that lead to all the products formed. Use curved arrows and indicate all formal charges. RR reaction name/type reaction name/type 1.MPBA 2. 2, + 7

8 omplete the following reactions: A d d i t i o n R e a c t i o n s reaction name reaction name 2 Pt Zn hot KMn 4 reaction name 1.g(Ac) 2, 2 2.NaB 4 reaction name omplete the reactions by writing in the above the arrow. 2 A. 2 epoxide. 2 l 2 B. D. Give the best reagent or set of for each transformation. a b 3 =2 3 3 c 3 d a. b. c. d. I 4, Δ omplete the following reactions: 1.B 3 TF , Pt, D 2 show correct stereochemsitry l 2 3, phase transfer catalyst 8

9 A d d i t i o n R e a c t i o n s - o n d i t i o n s 2 L. B. K. A.. J. 2 D. I. G. E.. F. l A. LDA A. Na B. Nal acetone Na. Nal acetone. LDA I 9

10 s R e a c t i o n s omplete by filling in the missing, condition(s) and/or product(s) l K Δ ( 2 )( ) K Δ 2 (E) alkene ot KMn K t-buk potassium t-butoxide 1.MPBA specify stereochemistry 2 1.g(Ac) 2, 2 2.NaB 4 2 S 4 Δ l 2 l 1.MPBA , + & 3 & l 10

11 S y n t h e s i s Starting from, give a reasonable synthesis the following: synthesize starting from synthesize starting from synthesize starting from l synthesize starting from starting from l synthesize 11

12 S A MP L E Q UIZ a. Give a stepwise mechanism for the following reaction. Your mechanism should show individual steps in the reaction that lead to all the products formed. Use curved arrows and indicate all formal charges. b Draw a representative potential energy curve that correctly shows your mechanism. Label important intermediates and transition states on your potential diagram energy reaction time 2. Give the best reagent or set of for each transformation. 2 a b c d = a. b. c. d. I 4, Δ 12

13 3. omplete the following reaction and show correct stereochemistry where appropriate. reaction name reaction name show correct stereochemsitry cold KMn 4 - Pt, D 2 show correct stereochemsitry l 2, 2 3, phase transfer catalyst 4. Give the needed the formation of the products under the given. peroxyacetic acid 2, + (±)-2,3-pentanediol 2 hv 5. Starting with the compound on the left, show synthetic steps that lead up to the target molecule on the right. 13