Question

please explain as well, thank you.

(8) 1. Draw all the molecular orbitals for the X-system of the allyl anion. Indicate which orbital is the HOMO. (20) 2. Provide reasonable product structures for the following reactions. Indicate clearly if you expect one isomer to predominate. NBS/ROOH D-Br (1 mg) +25°C (1g) -40 °C ) Br (1 e -78 "C (12) 3. Provide product structures for the following Diels-Alder reactions. The second Diels-Alder product eliminates a neutral substance upon further heating. Identify that substance. COOMe Meo. heat more heat COOM COOME COOM Ch.0- (10) 4. For the following pairs of compounds, select the one that better fits the description and provide a brief explanation for your selection. more likely to undergos Diels-Alder reaction with maleic anhydrides (10) EXTRA! Adamantene (shown below) has never been isolated, but evidence for its formation has been seen because it decomposes how a reverse Diels-Alder reaction. Draw the product of the reaction and explain why the forward Diels-Alder reaction is unlikely to occur. reverse Diels-Alder

Answer 1

label orbitals 41-43 in increasing energy *-- this is the LUMO two nodes energy 3 x 2p -- this is the HOMO one node put four electrons into the lowest energy orbitals combine TL 41

11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Saturday 09.00 NBS NBS Br By ROO 10.00 c. Dr Br 10 CH2 11.00 Br D-Br (1 egg +25°C Br. (tea) 12 00 - 7800 01.00 CN 02.00 5 03.00 04.00 coane -come e hear meal heak. UT meo. khoone t o =c=0 05.00 lo que evne ENCA 07.00 o is more stable than . Because ③ Sunday 10 is locked in socis conformation, so it can undergo Diels-Alder reaction & hence not stable. is locked in s-eis conformation which is necessare for Diels alder reaction. NOTES: 5