[Nekromantis]

Hi, I have to receive Griseofulvin in double Michael Addition. I have a two compounds. Addition is in presence t-BuOK and t-BuOH.

I wrote the mechanism. It's correct?

[TwistedConf]

I wrote the mechanism. It's correct?

No.

Lots of problems here. You even wrote a structure with 5 bonds to carbon.

Your best bet is to start over and think about it one step at a time-- perhaps starting by working backwards.  Looks like the enol ether is throwing you off, too. You need to review your material about quenching the Michael intermediate.

What about the product stereochemistry?

[Nekromantis]

I think, that my worst problem is ether group, because i can't write resonanse structure in first steps

[TwistedConf]

The only thing that resembles a correct step with all curved arrows drawn correctly is your second step, where the carbanion attacks the unsaturated beta carbon.

Otherwise, there are many errors in strategy, structure, and mechanism drawing. You need to start over and re-evaluate your strategy and mechanism drawing-- particularly how you will accomplish the ring closing.

[Nekromantis]

Could you write me this mechanism?

[Dan]

Could you write me this mechanism?

We don't do answer dumps here. Try again and we will help you.

Start by studying the basics of the mechanism - see for example:

http://www.organic-chemistry.org/namedreactions/michael-addition.shtm
http://en.wikipedia.org/wiki/Michael_reaction

[Nekromantis]

I know mechanism Michael addition but I can't apply to this exemple.

1. t-BuO(-) attacking atom of hydrogen
2. Nucleophile attacking atom of carbon at double bond. This double bond goes to single bond at carbonyl carbon.
3. What now? This double bond is disrupted by basic?

sorry for my english, but I'm from poland

[Nekromantis]

I wrote a new mechanism. It's now correct?

And I have a one question. Now i thinking, that first should be breake triple bond and next double. Yes?

[orgopete]

Better, but I'd be inclined to reverse which conjugate addition occurs first. For example, can the enolate reach the carbon of the acetylene? Although I understand the mechanistic inferences, it is difficult to distinguish between a person's difficulty in deducing a mechanism and the imprecision of the curved arrow usage causing it. Who would end a curved arrow at the "t" of t-butanol? This is like writing a mechanism despite what the curved arrows indicate.