Transition-state geometry and stereochemistry of the ene reaction between olefins and maleic anhydride

Abstract

But, equally important, the culture in the company gradually evolved to becoming much more open, less defensive, a truly learning organisation. What nextDutch National Quality Award the management team decided to re-embark on a renewed company wide program in order to reach new platforms in Total Quality.In the autumn of 1993, even after winning the first Main topic: New Developments in Oleochemical Research, Technology and Application J . 0 . M e t z g e r and Ursula B i e r m a n n , Oldenburg: Ene additions to unsaturated fatty compounds Thermal reactions of unsaturated fatty compounds e. g. of oleic acid and erucic acid with maleic anhydride are well known'. ' . The reaction is called "maleinization" and takes place by forming a new C,C-bond with migration of the ene double bond and 1,s-hydrogen shift. The diastereoselectivity of the reaction has not yet been examined.We carried out the addition of maleic anhydride to oleic acid (180°C, 24 h) and obtained the ene adduct in an isolated yield of 75%. The addition takes place in positions C-9 and C-10 of the molecule chain. The regioisomers were obtained as a mixture of diastereomers as pure (E)-adducts in a ratio of 1:l. The ratio of threo-and erythro-adduct was 4:l. The assignment could be made definitely using I3C-NMR by comparison with literature data3. 0 3 1 '*ooC' 24b + 0 'J. 0. Metzger u. K . E Leisinger, Fat Sci. Technol. 90, 1 [1988].

Synthesis of alkenyl succinic anhydrides from methyl esters of high oleic sunflower oil

“…FTIR spectra of ASA2S presented the representative bands of the expected groups. The major infrared bands arising from anhydride carbonyl stretching were located at 1785 cm 21 and 1863 cm 21 . Also, a stretch vibration band typical of five-membered cyclic anhy- drides (succinic anhydride) was shown at 917 cm 21 .…”

“…The major infrared bands arising from anhydride carbonyl stretching were located at 1785 cm 21 and 1863 cm 21 . Also, a stretch vibration band typical of five-membered cyclic anhy- drides (succinic anhydride) was shown at 917 cm 21 . The carbonyl stretch band of the alkyl ester appeared at 1732 cm 21 .…”

“…Also, a stretch vibration band typical of five-membered cyclic anhy- drides (succinic anhydride) was shown at 917 cm 21 . The carbonyl stretch band of the alkyl ester appeared at 1732 cm 21 . Finally, a stretch vibration band was presented at 970 cm 21 , typical of a trans-configurated alkene double bond.…”

Esterification of Carboxylic Acids and Diacids by Trialkyl Borate under Solvent and Catalyst‐Free Conditions

“…15,16 An autoclave equipped with an agitator, an internal and an external thermometers, a manometer, and a safety valve was charged with 1-hexene (328 g, 4 mol), maleic anhydride (98 g, 1 mol) and phenothiazine (0.001 g). Temperature was raised to 210 ℃ in a period of 1 h and maintained at this temperature for additional 11 h. The reaction mixture was subjected to distillation under an atmospheric pressure in order to remove excess of 1-hexene and followed by vacuum distillation to separate the main product, trans-(2-hexenyl)succinic anhydride, (b.p.…”

Derivatives of Cardanol through the Ene Reaction with Diethyl Azodicarboxylate

“…In the ene reaction, an electron-deficient olefin forms a bond with an olefin that contains an allylic hydrogen. [22][23][24] It represents a group transfer pericyclic reaction and is related to Diels-Alder reaction. Because of its simplicity, it is a useful tool for the synthesis of complex molecules.…”