Synthèse de γ-lactames et de perhydro-1,2-pyridazin-3-ones polyfonctionnels.

Stereoselective Synthesis of Functionalized 1,4-Dienes

“…We have previously reported the substitution of Baylis-Hillman acetates of type 1 by various nucleophilic reagents (i.e., Grignard and Gilman reagents, lithium ester enolates, [1] 1,3-diketone salts, [2] primary and secondary amines, [3] and sodium nitronates). [4] This procedure provides a solid carbon-carbon bond-forming reaction in organic chemistry, leading to a reliable method of obtaining some biologically active compounds (a-methylene-d-valerolactones 2, [1] ( AE )-sarkomycin 3, [5] and ( AE )-mitsugashwalactone 4 [6] ) (Scheme 1).…”

Application of the acetate of baylis‐hillman adducts in the synthesis of 3‐carbomethoxy‐2H‐thiochromenes

“…Studies have focused on the S N 2 nucleophilic substitution of the BH adducts with a variety of nucleophiles. Many heterocycles have been synthesized including quinolines [12], dihydroquinolines [13], quinolones [14], pyrrolidines [15], cumarines [16] and indoles [17]. It was reported that 2,2 -dithiodibenzaldehyde could be used as a masked thiosalicyl aldehyde in the BH reaction with activated alkenes in the presence of 1, 8-diazabicyclo-[5,4,0]undec-7-ene (DBU) to give thiochromenes [18].…”

Synthesis of 3-Nitro-1H-indole-2-carboxylic Acid Ethyl Ester Derivatives from Baylis-Hillman Adducts

“…During the past several years, the Baylis-Hillman reaction has been extensively studied and is now one of the most efficient carbon-carbon bond forming reaction. 1 Many heterocycles have been synthesized from Baylis-Hillman adducts (BH adducts) including quinolines, 2 dihydroquinolines, 3 quinolones, 4 pyrrolidines, 5 and recently indoles albeit in low yields and under harsh conditions. 6 Despite some interesting properties as intermediates for the preparation of pharmacologically active compounds, 7 3-nitro-1H-indole-2-carboxylic acid ethyl ester derivatives have been relatively poorly studied probably because of disappointing preparation procedures 8 in terms of regiochemistry and yields (nitration reaction).…”