Page 08 23. (CH3)3CBr + OH− ↓ (CH3)3COH + Br− The above reaction proceeds via an SN1 mechanism. What effect will doubling the concentration of hydroxide ions have on the reaction rate? A It will have no effect. B The reaction rate will halve. C The reaction rate will double. D The reaction rate will increase by a factor of four. 24. H C H H C H H C O O H Which of the following shows the splitting pattern for the circled H atom above, in a high resolution proton NMR spectrum? A B C D Page 09 25. HO OH C H OH C H H N H H OH C H OH C H H N CH3 H C H OH C H CH3 N H H Noradrenaline Phenylephrine Amphetamine Noradrenaline and phenylephrine stimulate receptors in the body resulting in increased blood pressure. Amphetamine has the same effect but works indirectly in the body by stimulating production of noradrenaline. The structural fragment acting directly on the receptor is OH C H C H H N H OH C H C H H N H H C H OH C H N H OH C H OH C H H N H A B C D [Turn over