A simple, convenient and highly stereoselective synthesis of diethyl (E)-1-(bromomethyl)-2-cyanovinylphosphonate 4 is described. The product would be a useful substrate for the synthesis of diethyl 1-[(alkylamino)(cyano)methyl]vinylphosphonates 5 via allylic rearrangement S N 2 -type mechanism.

Selected Reactions of Diethyl (E)-1-(Bromomethyl)-2-cyanovinylphosphonate with Secondary and Tertiary Amines. -The reaction of phosphonate (I) with less bulky secondary amines leads to phosphonates of type (III)/(IV) after substitution and rearrangement. More bulky secondary amines afford the normal substitution products of type (V). The reaction with tertiary amines affords phosphonate (VII). -(FRAY, A.; BEN KRAIEM, J.; AMRI*, H.; Heteroat. Chem. 24 (2013) 6, 460-465, http://dx.doi.org/10.1002/hc.21112 ; Fac. Sci. Tunis, Univ. El-Manar, 2092 El Manar, Tunis, Tunisia; Eng.) -M. Bohle 15-205

New and highly functionalized 1,3-dienes 3 and 4 have been synthesized via two different pathways starting from allyl bromide 1. Firstly, the reaction of allyl bromide 1 with triethylphosphite leads to an allylphosphonate 2, which undergoes the Wittig-Horner reaction with a range of saturated and unsaturated aldehydes gives rise to the corresponding 1,3-dienes 3. Secondly, a highly stereoselective reaction between allyl bromide 1 and nitroalkane salts, offers the possibility to obtaining functionalized (E)-1,3-dienes 4.

An easy regio‐ and stereoselective synthesis of new nitrogenous molecules 2a–e was successfully realized via an effective coupling reaction of diethyl (E)‐1‐(bromomethyl)‐2‐cyanovinylphosphonate 1 with various secondary amines in methanol. Hence, the use of less and more bulky secondary amines gives rise, respectively, to the successive (SN2′) substitution–isomerization and (SN2) substitution derivatives 2a–c and 2d–e. Moreover, the addition of tertiary amines to 1 in the same reaction conditions, leads exclusively to the rearranged vinyl ether 3 in good yields.