grignard reagents

a. Give the reaction scheme, showing the products formed (before hydrolysis) when one equivalent of ethylmagnesium bromide is treated with one equivalent of 5-hydroxy-2pentanone. Does addition of two equivalents of Grignard reagent to this yield a different product(s)? If so, give the structure(s). b. Explain why Grignard reagents cannot be prepared from an organic halide that also contains a hydoxyl, a carboxyl, a thiol, or amino group. c. What would be the final product of the reaction between methyl benzoate and two equivalents of ethylmagnesium bromide? d. Consider the same reaction as in the case of question C except that it is carried out with ethyl benzoate. What product wo... click for more

grignard reagents

a. It is likely that the amount of Grignard reagent in analysis is greater than the amount of Grignard reagent actually present just before adding water. Explain. b. What hydrocarbon would you expect to obtain by the action of water on each of the Grignard reagents listed below? 1. Butylmagnesium bromide 2. sec-Butylmagnesium bromide 3. iso-Butylmagnesium bromide 4. tert-Butylmagnesium bromide c. What product would each of the Grignard reagents in the previous question (b.) yield when treated with D2O?

aldol condensation

a. "Crossed" or "mixed" aldol condensations are practical for synthesis, if one of the aldehydes (or ketones) has no alpha-hydrogen atoms. Explain. b. In the aldol condensation, why might it be essentail that the benzaldehyde contain no benzoic acid?

synthic reaction scheme

a. Outline a synthetic reaction scheme for the preparation of triphenylmethanol from: 1. Methyl benzoate 2.Diethyl carbonate b. A large number of polycyclic benzenoid aromatic hydrocarbons are known. One of these, benz/a/pyrene, is a powerful carcinogen found in tobacco smoke. Draw the structure of this hydrocarbon. Can you suggest other sources where this material might be expected to be present?

structures

a. If 3-bromo-1-propanol is treated with NaOH, a compound of molecular formula C3H6) is formed. Suggest a structure for this product. b. What product(s) would you expect to form when tetrahydrofuran is treated with excess hydroiodic acid (HI)? c. Write a suitable mechanism for the cleavage of butyl isopropyl ether with HI at 100 degrees C to form exclusively isopropyl alcohol and 1-iodobutane. Explain why butyl alcohol and isopropyl are not formed in this reaction.