Show the starting materials needed to obtain the following products using Claisen condensations:
8. Give products or required starting materials for these crossed-Claisen condensations that use two different esters. Note that the first ester is added to the base to form an enolate. (If the base were added to the ester, enolates would form and react with the ester present in the flask). Give the enolate for the first reaction. 1) O 2) OK iPro ОMe Meo t-butoxide THF 1) 2) N LÝ OMe Eto Meo LDA 1) 2) Meo Оме Eto LDA...
Predict the major products of the following crossed Claisen
condensations. (Do not draw any aldol byproducts.)
NaOCHẠCH CH,CH-C-CH2 + CH,CH,0-C-OCH.CH NaOCH CH3 CH, -C-CH,CH-C-OCH.CH
17. Propose starting materials needed to synthesize each molecule through a Claisen reaction. a. Eto = = OME OMe = = Ph = =
Question 4 1 pts Aldol and Claisen condensations are prone to "mixed products." Which of the following techniques can be used to help reduce the mixture of products one obtains in these reactions? O Make it so that one of the reagants does not have any "alpha protons." O Slowly add any reagants which you are concerned might readily self-react (react with themselves). O Heat the reaction up. OAll of the above. O 2 of the 3 above are correct.
3. Claisen reactions have the advantage of flexibility among starting materials. Show 2 different sets of starting materials that will make the given product via Claisen-type reactions. (21.5) llon 6. Show the Michael product formed from the aldol condensation product of ethanal plus the Claisen condensation product of ethyl acetate when they react together in the Michael reaction. (21.3; 21.5, 21.8) it + H ethanal ethyl acetate
17. Propose starting materials needed to synthesize each molecule through a Claisen reaction. a. Etor = = COMe = d. EO Y OEt f Ph TY = =
7. Show the starting materials, conditions, and steps to make each compound via Claisen reaction or Dieckmann cyclization: b OO OME OEt
Suggest the starting material needed to make the following β-dicarbonyl compound by a Claisen condensation.
Predict the products of the following aldol condensations. Show the products both before and after dehydration. (c) 2 PhầCHO + CH --CH, rot , (a) p-2_CH, + +eu ou
Draw the starting materials needed to form (CH3)2C=CHCH2CH3 using a Wittig reaction. Provide the products that result when (CH3)2NCH=C(CH3)2 undergoes hydrolysis in dilute acid.