What is the difference between hoffman and zaitsev

What is Saytzeff Rule 3. What is Hofmann Rule 4. Saytzeff rule is an empirical rule that determines the final product of a particular reaction as the most substituted product. This rule is important in predicting the substitution of the final alkene product obtained from an elimination reaction.

Therefore, the most substituted final product is the major product of the chemical reaction, which also turns out to be the most stable product. I have a problem related to Hofmann Elimination. Can you help me this exercises? It has the E configuration. Use stereochemical drawings of the transition states to explain these observations.

Lilly scientist, Butler un organic lecturer discovered sunday that stork had died at 95 yrs old. Could you please explain why this reaction too yields a Hofmann product? Any hints towards the probable mechanism please? Thanks in advance. POCl3 gives a phosphate leaving group. One other example where it has been observed is in eliminations adjacent to the steroid nucleus, as shown by Djerassi and co-workers. See Giner, J. J Org Chem. However, dehydration of 22 f?

Figure 3 shows a Newman projection rationalizing the product. Would you say that it is also a valid explanation? Hi Johann — that is a perfectly good explanation, and possibly a more rigorous one. The positively charged nitrogen is a strong electron withdrawing group, which increases acidity of the beta hydrogens. However the basicity of the tertiary hydrogen will be less, since it is made more electron-rich by its adjacent alkyl groups. I would like to ask if this identification was made correctly.

Of course, it is known that tautomerisation would occur for such an alkene product as it is an enol. However, let us ignore this fact in this case. Sign up to join this community.

The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Do you think any of the products will be the major outcome of the following E2 reaction as they are both yielding a double bond with the same degree of substitution? Explain your answer. Despite using a sterically unhindered base — OH , the Hoffman product appears to be predominant in the following E2 reaction.

Identify the Hofmann and Zaitsev products and explain this observation. If yes In what timings I can order it? Notify me of followup comments via e-mail. You can also subscribe without commenting. So, one product is going to be the alkene where the double bond is in the middle: On the other hand, the hydrogens on each methyl group give the same alkene since they are equivalent as confirmed by the symmetry plane and the structure of the alkenes: What is interesting is it turns out that only one of these two alkenes is the major product.

The ratio is about in favor of the more substituted alkene: The reason for this is the stability of the alkenes. Adding groups on the double bond increases the stability of the alkene: Now, checking our products, we can see that it is a mixture of a trisubstituted alkene with a disubstituted alkene and the trisubstituted alkene is the major product of this elimination reaction: So, the more substituted alkene is the major product of E2 elimination because of its higher stability.