A chemist allows some pure (2S,3R)-3-bromo-2,3-diphenylpentane to react with a solution of sodium ethoxide (NaOCH2CH3) in ethanol. The products are two alkenes: A (cis-trans mixture) and B, a single pure isomer. Under the same conditions, the reaction of (2S,3S)-3-bromo-2,3-diphenylpentane gives two alkenes, A (cis-trans mixture) and C. Upon catalytic hydrogenation, all three of these alkenes (A, B, and C) give 2,3-diphenylpentane. Determine the structures of A, B, and C, give equations for their formation, and explain the stereospecificity of these reactions.
The weights of students in a class of ten are: 120 130 160 170 200 210 190 190 140 calculate the standard deviation for the data. (5 marks) The table below shows the distribution of weights of 140 students joining a certain university: Weight (in pounds) Frequency 80-89 4 90-99 23 100-109 49 110-119 38 120-129 17 130-139 6 140-149 3 Plot a histogram for the above data.
February 6, 2016
4:39 am
Read More »
