Chiral carbene approach to gold-catalyzed asymmetric cyclization of 1,6-enynes

Matsumoto, Y.; Selim, Khalid B.; Nakanishi, Hiizu; Yamada, Ken‐ichi; Yamamoto, Yasutomo; Tomioka, Kiyoshi

doi:10.1016/j.tetlet.2009.11.039

Cited by 99 publications

(45 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All these complexes were tested as enantioselective catalysts in two reactions, a furanyne cyclization and an enyne cyclization. With ee values of 21% for the NAC-complex (R)-(S p )-10 in the furanyne cyclization the results are inferior to the known results with phosphane ligands [14], with 52% for the NAC-complex (S p )-8 the results in the enyne cyclization are comparable to the values published for the best NHC-gold(I) complex for this reaction [15,16].…”

Section: Resultsmentioning

confidence: 65%

See 1 more Smart Citation

Chiral [2.2]paracyclophane-based NAC- and NHC-gold(I) complexes

Göker

Kohl

Röminger

et al. 2015

Journal of Organometallic Chemistry

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 65%

“…The second test reaction was the addition of methanol to an enyne substrate. With chiral NHC-gold complexes already good ee values have been described [15,16].…”

Section: Catalytic Reactionsmentioning

confidence: 99%

Chiral [2.2]paracyclophane-based NAC- and NHC-gold(I) complexes

Göker

Kohl

Röminger

et al. 2015

Journal of Organometallic Chemistry

View full text Add to dashboard Cite

“…The vast majority of Au(I)-catalyzed asymmetric reactions developed have utilized enantioenriched axially chiral bisphosphine ligands ( i.e. BINAP, SEGPHOS, and BIPHEP derivatives), 14 although reports using chiral phosphoramidites/phosphites, 15 and N -heterocyclic carbene 16 ligands have also been published. We were forced to exclude potential candidates from these classes because earlier ligand screening revealed that even the relatively unhindered parent BINAP ligand was unable to catalyze 5- exo-dig cyclization.…”

Section: Enantioselective Alkynylationmentioning

confidence: 99%

Enantioselective synthesis of cyclic carbamimidates via a three-component reaction of imines, terminal alkynes, and p-toluenesulfonylisocyanate using a monophosphine gold(i) catalyst

2011

View full text Add to dashboard Cite

A racemic Au(I)-catalyzed three-component reaction has been developed to prepare cyclic carbamimidates from imines, terminal alkynes, and sulfonylisocyanates. This reaction exploits the carbophilic π-acidity of gold catalysts to first activate an alkyne toward deprotonation and secondly, to activate the internal alkyne generated toward intramolecular O-cyclization. Unlike similar previously reported multicomponent gold-catalyzed reactions, the stereocenter generated during the alkynylation is preserved in the product. This trait was exploited by developing an enantioselective variant, using an unusual trans-1-diphenylphosphino-2-arylsulfamidocyclohexane ligand. Moderate to excellent levels of enantioselectivity were obtained using a variety of N-arylbenzylidene anilines (41–95% ee, 18 examples).

show abstract

“…In the case of Au(I) catalysts, a promising enantiomeric excess was obtained in the presence of the (R)-Tol-binap-gold chloride complex 235 but the scope was limited to the carbon-bridged derivative 233. Other approaches involving the in situ preparation of the (phosphine)Au(I) complexes from AuCl 3 [173] or the use of chiral N-heterocyclic carbene gold complexes [174] have resulted in moderate enantioselectivities. Other approaches involving the in situ preparation of the (phosphine)Au(I) complexes from AuCl 3 [173] or the use of chiral N-heterocyclic carbene gold complexes [174] have resulted in moderate enantioselectivities.…”

Section: Scheme 42 Regioselectivity In the Domino Alkoxylation/cycloimentioning

confidence: 99%