The low-valent titanium reductive elimination reaction, already applied to the stereospecific synthesis of vitamin A and 13-cis-retinol, was used to prepare several retinoic acid analogues in the all-trans configuration or in the 13-cis configuration. This highly stereospecific trans-diene formation allowed an improved synthesis of the title compounds without any purification of the intermediates before the final stage. all-trans-Retinoic acid ...
![2-methyl-4-[(2',3',5'-trimethylphenyl)oxy]-2-butene Structure](https://image.chemsrc.com/caspic/001/119947-52-3.png)
