Addition reactions of dienes

Tridentate salen ligands (10) derived from 1 have given excellent results in the enantiocontrol of the hetero Diels-Alder addition reaction of dienes with aldehydes (eq 7) and in the asymmetric additions of TMS-azide to mc5o-epoxide and trimethylsilyl cyanide to benzaldehyde (up to 85% ee). Phosphino-oxazolines derived from 1 have been employed for the asymmetric control of palladium-catalyzed allylic substitution reactions products of 70-90% ee were obtained. Photolysis of crystalline adducts of enantiomerically pure 1 with prochiral alcohols results in asymmetric inductions of up to 79% in a rare example of a solid-state enantioselective reaction. ... 

One area of noteworthy activity during the year, if only because of the number of relevant publications, has been that concerning addition reactions of (diene)-phosphonic acid derivatives [particularly those of (l,2-propadiene)phosphonic... 

There are many possible schemes for addition reactions of diene monomers from electronical and steric viewpoints. Because the monomer molecules arrange along the direction of the channels, a,co-addition may selectively take place in one-dimensional inclusion polymerization. Therefore, conjugated polyenes, such as dienes and trienes, may selectively polymerize by 1,4- and 1,6-addi-tion, respectively. 1,3-Butadiene polymerized via 1,4-addition exclusively in the chaimels of urea and perhydrotriphenylene. while the same monomer polymerized via both 1,2- and 1,4-additions in the channels of deoxycholic acid and apocholic acid. Moreover, we have to evaluate head-to-tail or head-to-head (tail-to-tail) additions in the case of dissymmetric conjugated diene monomers such as isoprene and 1.3-pentadiene. 

---

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ , ]

---