2.3 Propose a mechanism for the reaction below: :0: : 0: u EtO 1) EtONa, EtOH 2) Br(CH2)5Br OEt 3) NaOH 4) HCI, H₂O Δ : 0: OH

i) ii) 1. Propose a mechanism for the following reactions. H (CH3)2NH H* NaOH EtOH

Propose a plausible mechanism for the following chemical transformation: CI excess NaOH

Provide a mechanism for the following reaction 1. DE+ & +- & •H 2.430+

1. Propose a mechanism for the following transformation: R COOH (1) H₂C-O, (C₂H₂)₂NH (2) H₂O, acetate buffer R CH₂

Draw a curly arrow mechanism for the reaction below and hence predict the structure of K. (c) 1) PCI, 2) NAOME CyH,NO

Treatment of acetylene with a suitable base affords lithium acetylide, which was used as a reagent in a partial synthesis of the antitumor natural product (+)-acutiphycin. (Org. Lett. 2014, 16, 1168-1171) Possible bases to consider H-C=C-H Acetylene Step 1 Li :Base T H-O: Li Lithium hydroxide (LiOH) three steps Lithium acetylide Draw the structure of lithium acetylide. Draw Your Solution di. Η Η Η Η | | | | H-C-C-C-C: II HH HH Butyllithium (BuLi) OR CEC- Li OH CH3 -H CH3 Lithium diisopropyl amide (LDA) OMe H3C H H₂C many steps Li HO OH I (+)-Acutiphycin CH3 CH₂ "OH

Propose a reasonable mechanism for the reaction below. Ph COOH D₂SO4 D₂O Ph D

Provide the mechanism for the following reaction (1) PhMgBr (2 equiv) (2) H3O+ workup OH

Identify compounds A and B from the following reaction sequence LINH lig MeO 0 (Ozone) MeOH Me₂S B