Question

Instructions: *Answer all four problems directly on this quiz. You may use your notes and textbook to answer the problems. Each problem is worth 5 points. .Hand in your answers before class on Tuesday Oct. 10th Problem, #1 The specific rotation of pure L-threonine at 25 ℃ is: [al,--28.3 ( 1.1 in CHCI, l-1.0 dm. a) What is the percent enantiomeric excess (ce) of a sample with a specific rotation of (alo-16.8 b) What are the percentages of (+)and ()enantiomers present in this sample? Problem #2 Draw arrows to carbons and/or bonds and identity the stereochemistry (using the E/Z and R/S descriptors) in the molecule shown below. O OH 0%

Answer 1

Answer for 5.

Soladtion: ch ch ct2 CH 3 HO oH mandom OH I R, 2R) , (2s,35) on PR 25, 35) 2S