- Enantioselective N-Heterocyclic Carbene Catalyzed Synthesis of Functionalized Indenes
-
An enantioselective NHC (N-heterocyclic carbene) catalyzed synthesis of indenes from bifunctional α,β-unsaturated acyl fluorides and TMS enol ethers has been discovered. The reaction has broad generality (31 examples) and proceeds with high levels of enantioselectivity (most >92:8 er). Mechanistically the reaction likely occurs via a Michael/β-lactonization/decarboxylation sequence. Derivatization studies and limitations are discussed.
- Zhang, Changhe,Lupton, David W.
-
supporting information
p. 4456 - 4459
(2017/09/11)
-
- Cobalt-catalyzed enantioselective intramolecular hydroacylation of ketones and olefins
-
Cobalt-chiral diphoshine catalytic systems promote intramolecular hydroacylation reactions of 2-acylbenzaldehydes and 2-alkenylbenzaldehydes to afford phthalide and indanone derivatives, respectively, in moderate to good yields with high enantioselectivities. The ketone hydroacylation did not exhibit a significant H/D kinetic isotope effect (KIE) with respect to the aldehyde C-H bond, indicating that C-H activation would not be involved in the rate-limiting step.
- Yang, Junfeng,Yoshikai, Naohiko
-
supporting information
p. 16748 - 16751
(2015/02/05)
-
- Phthalides by rhodium-catalyzed ketone hydroacylation
-
(Chemical Equation Presented) Phthalides are biologically relevant five-membered lactones found in herbs, fruits, and vegetables. Herein we communicate the first atom-economical approach to phthalides by using enantioselective ketone hydroacylation. In the presence of Rh[(Duanphos)]X (X = NO3, OTf, OMs), various 2-ketobenzaldehydes undergo intramolecular hydroacylation to produce phthalide products in good yields and 92-98% ee's. Our study highlights the key role counterions play in controlling both reactivity and enantioselectivity. A concise asymmetric total synthesis of the celery extract (S)-(-)-3-n-butylphthalide is also presented.
- Phan, Diem H. T.,Kim, Byoungmoo,Dong, Vy M.
-
supporting information; experimental part
p. 15608 - 15609
(2010/01/30)
-
- 2,3-Dihydro-5-alkoxy-5-phenyl-5H-imidazo[2,1-a]isoindoles
-
Novel 2[2-(1,3-diazacycloalk-2-enyl)]benzophenone compounds and novel 1,3-diazacycloalkenyl[2,1-a]isoindole compounds having useful analgesic and psychostimulant properties are prepared inter alia by condensation of o-benzoylbenzaldehydes with aliphatic diamines.
- -
-
-