Dat Destroyer Ochem question number 52

[Mrhyde]

NaOCH3 I have always seen favor E2 but in this problem on page 21. it favors SN2 ??

 

[Dre4m3r]

NaOCH3 is a both strong nuc and base so can do E2 and SN2, so it depends on the electrophile here. if you have tertiary alkyl halide E2 is favored while primary favor SN2. secondary produce mixture of sn2 and e2.
hth. sorry i dont have your version of destroyer.

 

[DAT Destroyer]

NaOCH3 I have always seen favor E2 but in this problem on page 21. it favors SN2 ??

I love a perspicacious student ! Indeed so, Secondary and Tertiary substrates love to do E2 when treated with NaOCH3 or NaOC2H5.....but SN2 always competes. Since there is no E2 choice, go for the SN2 product. As a matter of fact, in Advanced Organic Chemistry, we learn that SN2 is actually slightly favored when a Tos group is present on a secondary substrate !!! Author Michael B. Smith of the University of Connecticut wrote that the reasons are not totally understood . Bottom line.....E2 and Sn2 compete with each other and E2 always wins if heated , Sn2 wins if Tos is present. If no heat.....It can be close, but E2 is usually favored !!!

Hope this helps.

Dr. Romano

 

[Mrhyde]

I love a perspicacious student ! Indeed so, Secondary and Tertiary substrates love to do E2 when treated with NaOCH3 or NaOC2H5.....but SN2 always competes. Since there is no E2 choice, go for the SN2 product. As a matter of fact, in Advanced Organic Chemistry, we learn that SN2 is actually slightly favored when a Tos group is present on a secondary substrate !!! Author Michael B. Smith of the University of Connecticut wrote that the reasons are not totally understood . Bottom line.....E2 and Sn2 compete with each other and E2 always wins if heated , Sn2 wins if Tos is present. If no heat.....It can be close, but E2 is usually favored !!!

Hope this helps.

Dr. Romano

Wow amazing answer and explanation ! Thank you so much 🙂 Yep it did not occur to me to just assume SN2 since E2 was not an option for the answers because of the tricky choice E which was none of the above. But now I understand from your explanation , thanks again

 

[DAT Destroyer]

Wow amazing answer and explanation ! Thank you so much 🙂 Yep it did not occur to me to just assume SN2 since E2 was not an option for the answers because of the tricky choice E which was none of the above. But now I understand from your explanation , thanks again

Glad I could help!

Dr. Romano

 

[nwanheg]

Yep it did not occur to me to just assume SN2 since E2 was not an option for the answers because of the tricky choice E which was none of the above