title: Regioselectivity control in a ruthenium-catalyzed cycloisomerization of diyne-ols.
abstract: The ruthenium-catalyzed cycloisomerization of diynes containing one silyl alkyne and one propargyl alcohol yields 2-silyl-[6H]-pyrans instead of the expected unsaturated acylsilanes except when additional conjugation of a aromatic ring is present at the delta-position. Under certain conditions, a facile ruthenium-catalyzed isomerization of the product takes place as well. This regioselectivity of the cyclization can be controlled by the choice of solvent system. DFT calculations confirm the expected greater stability of the silyl-pyrans relative to the acylsilanes.
authors.affiliation: Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
authors.forename: Barry M
authors.initials: BM
authors.lastname: Trost
authors.forename: Michael T
authors.initials: MT
authors.lastname: Rudd
authors.forename: Moisés Gulías
authors.initials: MG
authors.lastname: Costa
authors.forename: Philip I
authors.initials: PI
authors.lastname: Lee
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Pomerantz
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D007536:Isomerism; D020005:Propanols / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D000480:Alkynes; D020005:Propanols; D012428:Ruthenium; C028255:propargyl alcohol