Mountain_Girl
(Newbee) 03-05-02 11:59 No 277131 |
2,5-Dimethoxy Phenylacetic acid from Hydroquinone | Bookmark | ||||||
While swim struggles to dream up tried and tested synths she has wondered if anyone has considered: 1. Hydroquinone + Acetic Anhydride __> Hydroquinone Diacetate, 91 % yield [Synth in Vogel] 2. Hydroquinone Diacetate + AlCl3 __> 2,5-Dihydroxy Acetophenone, 58% yield [Synth in Vogel] 3. 2,5-Dihydroxy Acetophenone + DMS __> 2,5-Dimethoxy Acetophenone [should be straight forward afaik] 4. 2,5-Dimethoxy Acetophenone + S + Morpholine __> 2,5-Dimethoxy Phenylacetic Acid [Willgerodt-Kindler, not sure how well this would work. The analogous compound from p-methoxy acetophenone is prepared in 63% yield in Vogel] Admittedly this route requires reagents (Acetic Anhydride, DMS, Morpholine) which most bees (including swim) do not have access to. |
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Rhodium (Chief Bee) 03-05-02 15:15 No 277164 |
Re: 2,5-Dimethoxy Phenylacetic acid from Hydroquinone | Bookmark | ||||||
I think it's a sound, workable idea, if you don't mind the H2S from the Willgerodt reaction. You can use acetyl chloride instead of the anhydride for the esterification, Antoncho have pioneered the use of H2SO4/MeOH/Na2SO4 as a methylating agent for phenols, and morpholine is easily made from diethanolamine (see my page). |
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