Question

organic chemistry.

1. please show the work (may draw this into other configuration to show)

CH3 H HOICH3 H3CHCH2OH HYH ΗΤΗ OH IU OH CH3 H3C 413 II HY HT CH3 Which of the Newman projections (A - E) depicted above corresponds to (S)-butan-2-ol, looking from C3-C2? Projection A Projection B Projection Projection D Projection E

2. please show work

Answer 1

Option B is the correct answer for question 1.
Bluchere of beltan-2-ol en Fisclat opojection : chain tason Jaana CH3 eh. CH2 ACH The c-2 is chiral as it has 4 a different groups atached and hence it needs to be configured. Rules fan assigning priority sequence : 1. Higher the atomic no. of the atom attached to cambon higher is the priority. 2. If 2 atomo directly linked to the chinal centre becomes same then next set of alom is considered & this process goes on until a point of difference is reached 3. The atoms are labelled in priority sequece a—b ed. oy Now keeping din homizontal position if a b c pathway is clockwise then s, if anticlockwise R.

HA Msing the above rules we get a possible configurational a sbructures : & JOH H00 H снэ. CHZ. a be is clockwise (S)-butan-2-ob. arbee is anti-clockwise .. (R)-butan-2-of Molecule geven in question. Structure of (S)-butan-2-of in Fischer projection and its subequent conversion to waw-honse projecton looking from 63-02:n. 1 CH₂ CH 4 2.0 OH # ICH3 eme 4 CH3 : 1 ACHZ Saw.house Fischer

Conversion of Saw honse to Necoman projection : - CH3 CH3 с 16Hz CH3 (Sau honse) (Newman). . eclipsed. a eclipsed 1 Hootz W # # 60° rotation fe2. Staggered optian B Note: The eclipsed form is changed to xlaggened form via 60° rotation of C2 along CB-62 bond. This is done to minimise Aftorie repulsion bederen 2 - elp group.