99930-84-4Relevant articles and documents
Asymmetric approaches to cyclopentenones in the Ni(0)-promoted cyclocarbonylation reaction of allyl halides and acetylenes
Villar, Juan Manuel,Delgado, Antonio,Llebaria, Amadeu,Moreto, Josep M.,Molins, Elies,Miravitlles, Carles
, p. 10525 - 10546 (2007/10/03)
Different approaches to the asymmetric synthesis of cyclopentenones by means of the Ni(CO)4-promoted alkyne-allyl halide cyclization-carbonylation are reported. The use of acetylenic sulfoxides 1 has proved effective for the synthesis of acyclic, fused [5+8], and spiro [5+5], [5+7], and [5+8] cyclopentenones, whereas placement of the aryl sulfoxide on the allylic system failed to afford any cycloadduct. Homochiral fused [5+8], and spiro [5+7] and [5+8] cyclopentenones have been obtained by this methodology. Finally, a modest enantioselectivity was observed when different homochiral α-substituted carboxylates were used as ligands in our reaction system.
Chiral acetylenic sulfoxide in alkaloid synthesis. Total synthesis of (R)-(+)-carnegine
Lee,Chan,Lee
, p. 6861 - 6864 (2007/10/02)
Remarkable diastereoselectivity was observed in the cyclization of β-aminovinyl sulfoxide 5a prepared from chiral acetylenic sulfoxide 1a in acidic medium. The cyclized product 6a was then converted to (R)-(+)-carnegine.
