Recent Advances in Stereoselective Synthesis of 1,3-Dienes

Abstract

The aim of this review is to present the latest developments in the stereoselective synthesis of conjugated dienes, covering the period 2005-2010. Since the use of this class of compounds is linked to the nature of their appendages (aryls, alkyls, electron-withdrawing, and heterosubstituted groups), the review has been categorized accordingly and illustrates the most representative strategies and mechanisms to access these targets.

Developing piperine towards TRPV1 and GABAA receptor ligands – synthesis of piperine analogs via Heck-coupling of conjugated dienes

“…An extension of the reaction time was not attempted in these cases, since the mass balance indicated significant decomposition of the starting materials. First, a set of four bases (NEt 3 , NaHCO 3 , K 2 CO 3 and NaOAc) and four solvents (MeCN, toluene, THF and DMF) were evaluated (entries [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. While toluene and THF did not facilitate coupling in combination with most bases, the best results were obtained with DMF as the solvent (entries 15-18).…”

Enantio‐ and Diastereoselective Synthesis of Chiral Allenes by Palladium‐Catalyzed Asymmetric [3+2] Cycloaddition Reactions

“…Additionally, we showcase the chemoselective reactivity and utility of the chiral allenes by rapidly transforming them to a variety of molecular architectures. Thus, the ruthenium‐catalyzed alkene–allene addition provides access to a synthetically important 1,3‐diene 8 in a fully regioselective manner (Scheme a). Notably, the allene 3 c underwent a rhodium‐catalyzed C−H activation reaction and delivered the densely functionalized diastereomeric products 10 a and 10 b (Scheme b).…”

Stereospecific Synthesis of Multi-Aryl Substituted Olefins and 1,3-Dienes via 1,4-Palladium Migration/Suzuki Coupling Sequence

“…9 Currently, the most common approach to obtain the corresponding pure individual isomer is through column chromatography. Despite the advancements in stereoselective synthesis of multi-substituted olefins 10, 11 and 1,3-dienes, 12,13 effective synthetic approaches toward multi-aryl-substituted ones remain to be limited, in which the application of symmetric starting material or a homo-coupling reaction is necessary to overcome the geometric problem. 14,15 Therefore, a more agile synthetic strategy to greatly expand the toolbox for advanced material discovery is highly desirable.…”