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Chemistry Forums for Students => Organic Chemistry Forum => Organic Chemistry Forum for Graduate Students and Professionals => Topic started by: Erythromycin on July 26, 2007, 06:08:21 AM

Title: Increasing self-Claisen condensation yields
Post by: Erythromycin on July 26, 2007, 06:08:21 AM

I'm trying to condense phenylpropionate into the corresponding beta keto ester. My yields are 5-15%. I have tried using both LDA and sodium hydride, varying the molar ratios of each. I have also tried temperatures up to 100 C. I do the work-up with acid following the reaction. Are there any Claisen experts out there who can help me? Thank you!

Title: Re: Increasing self-Claisen condensation yields
Post by: russellm72 on July 30, 2007, 01:21:45 PM

Haven't done one since i was doing my undergraduate studies and it wasn't self condensation. I used NaOMe/MeOH at reflux.

Have u checked the condition of your phenyl propionate? NMR and made sure its dry. I'm guessing its an oil and if so have u distilled it fresh prior to use.

R.