1 II. A synthesis for the preparation of compound 6 is proposed as below: 1. Please provide an electron-pushing mechanism for the formation of compound 3 from compound 1 (reaction 1). (16 points) OMeOOOHHOH+OMeOOHOOHHHOHOMeOOHOOHHOHHHOHHOMeOOHOOHHHOHOMeOOHOHHOOMeOOOHHOHOMeOOOHOHH Continue to the Next page OMeOOOOH+H2OOMeOOHHOCH3MgB r(2 equivalents)H+OOOHH+H2OOHHOOHO1356242(Re action 1)(Re action 2)(Re action 3)2 2. The proposed synthesis involves protection (reaction 1), nucleophilic addition (reaction 2), and deprotection (reaction 3). Will you expect to obtain the same final product, compound 6, if compound 1 is treated with the Grignard reagent, 4, (reaction 2) without going through the protection (reaction 1) first? Explain briefly your reason. (4 points) No. Ketone is more reactive than ester toward Grignard reagent. Continue to the Next page3 III. Propose an electron pushing mechanism for the following reaction. You have to show how to form the hydrazone intermediate. (20 points) OH2NNH2KOH, H2Oheating COH3CH2N NH2COH3CH2N NHHOHCOH3CH2N NHOHHO HCH3CHN NHOHO HHCH3CHN NO HHHOHCH3CN NHHO HHOHCH3CN NHHHOHO HCOH3CH2N NHHO
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