TY - JOUR
T1 - Chelate-assisted ring-closing metathesis
T2 - A strategy for accelerating macrocyclization at ambient temperatures
AU - Higman, Carolyn S.
AU - Nascimento, Daniel L.
AU - Ireland, Benjamin J.
AU - Audörsch, Stephan
AU - Bailey, Gwendolyn A.
AU - McDonald, Robert
AU - Fogg, Deryn E.
N1 - Funding Information:
This work was funded by NSERC of Canada. NSERC is thanked for fellowships to C.S.H., B.J.I., and G.A.B.
Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/2/7
Y1 - 2018/2/7
N2 - Ring-closing metathesis (RCM) offers versatile catalytic routes to macrocycles, with applications ranging from perfumery to production of antiviral drugs. Unwanted oligomerization, however, is a long-standing challenge. Oligomers can be converted into the cyclic targets by catalysts that are sufficiently reactive to promote backbiting (e.g., Ru complexes of N-heterocyclic carbenes; NHCs), but catalyst decomposition limits yields and selectivity. Incorporation of a hemilabile o-dianiline (ODA) chelate into new catalysts of the form RuCl2(NHC)(ODA)(=CHPh) accelerates macrocyclization, particularly for dienes bearing polar sites capable of H-bonding: it may also inhibit catalyst decomposition during metathesis. Significant improvements relative to prior Ru-NHC catalysts result, with fast macrocyclization of conformationally flexible dienes at room temperature.
AB - Ring-closing metathesis (RCM) offers versatile catalytic routes to macrocycles, with applications ranging from perfumery to production of antiviral drugs. Unwanted oligomerization, however, is a long-standing challenge. Oligomers can be converted into the cyclic targets by catalysts that are sufficiently reactive to promote backbiting (e.g., Ru complexes of N-heterocyclic carbenes; NHCs), but catalyst decomposition limits yields and selectivity. Incorporation of a hemilabile o-dianiline (ODA) chelate into new catalysts of the form RuCl2(NHC)(ODA)(=CHPh) accelerates macrocyclization, particularly for dienes bearing polar sites capable of H-bonding: it may also inhibit catalyst decomposition during metathesis. Significant improvements relative to prior Ru-NHC catalysts result, with fast macrocyclization of conformationally flexible dienes at room temperature.
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U2 - 10.1021/jacs.7b13257
DO - 10.1021/jacs.7b13257
M3 - Article
C2 - 29345905
AN - SCOPUS:85041894909
SN - 0002-7863
VL - 140
SP - 1604
EP - 1607
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 5
ER -