Question

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If a sample of the following compound was found to possess 20% ce, then what is the ratio of the major enantiomer to the minor enantiomer? o OH NH 5:1 4:3 QUESTION 4 3 points Consider the compound below, in the given conformation. From the perspective shown (sighting along the labeled C3-C4 bond axis), which of the following is the correct Newman projection? A) HẠC CH.CH CH B) CH.CH CH C) H HC CH2CH3 H D) CH.CH сн. Н. H CHE CH₂CHS H CH CH.CH HC HEC CH.CH "Η CH.CH А B ОООО D

Answer 1

It is based on concept of Sterisomerism.

activity. Given :- Concept is based optical One of enantiomes present in exess which o is Som (s-configuration) S ONH2 (major. Isomer) percentage enantiomeril excess 3 wees 200/ Let the enantiomer above shown be designated

as, %s'. Now, Since lee 520 o o .. .). S - . Rool.ee-20 We be know, the sum of ..s and loR must 100. (Since percentage is calculated on basis of 100) o %5 + J.Rs 100 2 Adding eg. © and eg. @ lie. 20 Is oors al. S t% R 100 20.3) : 120 %-53120 60 2 i e. %S = 60 (major enantiomer)

%s in eg. we Substituting value get of St. Rs100 YR; 100 -15 = 100-60=40 1 . ..S: 60 major enantiomer) % Ra 40% (minor Enantiomes S-enantiomera major Enantiomes : 60 100 R-enantioners minor Enantioner 40 Then Ratio = Major Enantiomer minor Enantiones 60/100 40/400 6 4 -: 3 2 Ratio = 3:2 3:2 is correct optim good is option correct.

4 Given compound is :- It can be drawn as in 3 4 Š the H han It can be 4 TH3 drawn Saw horse foorsmela as :- H 4 on CH3 H CH3 > H CHO с H₂ и 3 180° Rotation (-3-(-4 bond (Converted 'From Saw horse formula to Newman formula) Circle carbon. 0713 H H .CH H CH3 CH3 Tim Ho Dot CH₂ Hz Carbon (Newman formelda) (I) e Newman formelha of given compo und)

Now sotating e-3-(-u bond in various ways to match the given option, Rotating croele carbon so that -CH₂ CH3 group goes above we je get, ران си, сиз H CM3 H Rotate circled Carbon by 180° → CM3 the H Tina eta CH₂ CH3 (I) CH₂ CH3 clearly matches with this option 'D' compound. i option D will be correct answer. o D option is correct.
Please give me better rattings.

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