Synthesis of substituted 1,3-diene synthetic equivalents by a Ru-catalyzed diyne hydrative cyclization.
Catalyzed by [CpRu(CH3CN)3]PF6, the hydrative cyclization of dipropargylic sulfone substrates provides an effective way to synthesize highly functionalized substituted 3-sulfolenes. The amount of water is crucial for the reactivity of this cycloisomerization reaction. The scope and limitations of the Ru-catalyzed cycloisomerization are discussed. A marked ketone-directing effect was observed for the first time in ruthenium-catalyzed cyclizations. A plausible mechanism for the ketone-directed cycloisomerization is also rationalized. The utility of this method was demonstrated by both sulfur dioxide extrusion of the 3-sulfolenes to afford 1,3-dienes and subsequent inter- or intramolecular Diels-Alder reactions.
Trost
Barry M
BM
Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA. bmtrost@stanford.edu
Huang
Xiaojun
X
D000475:Alkenes / Q000138:chemical synthesis*; D000480:Alkynes / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods*; D003500:Cyclization; D007659:Ketones / Q000737:chemistry; D008956:Models, Chemical; D009942:Organometallic Compounds / Q000737:chemistry; D012428:Ruthenium / Q000737:chemistry*; D013450:Sulfones / Q000138:chemical synthesis / Q000737:chemistry*; D013458:Sulfur Dioxide / Q000737:chemistry
D000475:Alkenes; D000480:Alkynes; D007659:Ketones; D009942:Organometallic Compounds; D013450:Sulfones; D013458:Sulfur Dioxide; D002244:Carbon; D012428:Ruthenium