Question

10.54 (...) The addition of H-X alkenes has been shown to add predominately via syn-addition, as shown below. н Br H-Br Two chemists disagreed on whether or not syn-addition would happen on terminal alkenes as well. Suggest an experiment through which you could resolve this dispute. H HCI syn or anti? 10.56 (...) When alkynes are treated with water and bromide, a bromoketone is produced. Provide a plausible arrow pushing mechanism, which accounts for the formation of this product. z Br2, H2O 10.58 (...) A chemist attempted to do the following acetylide alkylation reaction, but was unsuccessful in several attempts, producing only the original starting materials in each case. Explain why the reaction didn't work. [We will learn one way to solve this problem in Chapter 13.] LH 1. NaNH2 LX Ph 2. HOC A Ph desired product never formed.