Question

1. Use curved arrows to show the mechanisms of formation of the substitution products in each reaction. Indicate stereochemistry of the products where necessary. [10 points] OCH3 DMSO BrH ♡ CH,CH,OH CH3CH2OH Br a Br NaOH NaOH THF

Answer 1

Mechanism of formation of substitution products ÓCH3 DMSO BY H In the given reaction Õ CH₂ is a strong nucleophile and DMSO is a polar aprotic solwent to the reaction will proceed via SN, Mechanion. SN2 reactions are stereo specific reaction nucleophile attacks on the Carbon opposite to the learaing group so, on reaction carbon inversion takes place which is called WALDEN INVERSION. 0 <H3 SO, бенз DMSO TRANSITION STATE Осм. FINAL PRODUCT

си, сирон unce, CH CHOH Lethand) is a alcohol and also a polar prolic vovent. So, the reaction will proceed by SN, reaction Mechanism. In SNg Mechanisen, we knoue that planar c formed to the muchoptile can arack both side. This Racamisation mill ocur. Idence reaction is. - Сан, он снено + + u e-ch, он - сч, са 1 ) р-си.- с. RACE MIC MIXTURE Ло-си-с-

Naon, Naon THE dere , THE (Tetra hydro furan) is polas aprocic solvent. The reaction will be vn reaction and proceed vice SN Mechanism. Idence, - Br Haor THE TRANSITION STATE FINAL PRODUCT

THE GIVEN QUESTION IS BASED ON SUBSTITUTION REACTION.SO FOR THAT WE SHOULD CHECK IT THAT THROUGH WHICH MECHANISM IT WILL PROCEED i.e SN₁ OR SN₂ MECHANISM.FOR THAT WE MUST CHECK THE RECTANT WHETHER THEY ARE GOOD NUCLEOPHILE AND THE SOLVENT IN THE RECTION i.e POLAR PROTIC SOLVENT OR POLAR APPROTIC SOLVENT.