104598-15-4Relevant articles and documents
Direct organocatalytic asymmetric reductive Mannich-type reactions
Zhao, Gui-Ling,Córdova, Armando
, p. 7417 - 7421 (2006)
A direct asymmetric reductive Manich-type reaction that allows for the formation of three contiguous stereocenters with high chemo-, diastereo-, and enantioselectivity is presented.
Concise asymmetric total syntheses of (?)-nuciferol, (?)-nuciferal, and (?)-dihydrocurcumene via Rh(I)-catalyzed boronic acid addition
Pal, Souvik,Khatua, Arindam,Das, Mrinal K.,Bisai, Vishnumaya
, (2021/01/25)
A general catalytic asymmetric total synthesis of aromatic bisabolane sesquiterpenes, (?)-nuciferol (ent-1c), (?)-nuciferal (ent-1d), and (?)-dihydrocurcumene (ent-1h) have been achieved in 5–6 steps in high chemical yields from commercially available (E)
Design and application of hybrid phosphorus ligands for enantioselective Rh-Catalyzed anti-markovnikov hydroformylation of unfunctionalized 1,1-disubstituted Alkenes
You, Cai,Li, Shuailong,Li, Xiuxiu,Lan, Jialing,Yang, Yuhong,Chung, Lung Wa,Lv, Hui,Zhang, Xumu
supporting information, p. 4977 - 4981 (2018/04/24)
A series of novel hybrid phosphorus ligands were designed and applied to the Rh-catalyzed enantioselective anti-Markovnikov hydroformylation of unfunctionalized 1,1-disubstituted alkenes. By employing the new catalyst, linear aldehydes with β-chirality can be prepared with high yields and enantioselectivities under mild conditions. Furthermore, catalyst loading as low as 0.05 mol % furnished the desired product in good yield and undiminished selectivity, demonstrating the efficiency of this transformation in large-scale synthesis.
Iminium Catalysis inside a Self-Assembled Supramolecular Capsule: Scope and Mechanistic Studies
Br?uer, Thomas M.,Zhang, Qi,Tiefenbacher, Konrad
, p. 17500 - 17507 (2017/12/15)
Although iminium catalysis has become an important tool in organic chemistry, its combination with supramolecular host systems has remained largely unexplored. We report the detailed investigations into the first example of iminium catalysis inside a supramolecular host. In the case of 1,4-reductions of α,β-unsaturated aldehydes, catalytic amounts of host are able to increase the enantiomeric excess of the products formed. Several control experiments were performed and provided strong evidence that the modulation of enantiomeric excess of the reaction product indeed stems from a reaction on the inside of the capsule. The origin of the increased enantioselectivity in the capsule was investigated. Furthermore, the substrate and nucleophile scope were studied. Kinetic investigations as well as the kinetic isotope effect measured confirmed that the hydride delivery to the substrate is the rate-determining step inside the capsule. The exploration of benzothiazolidines as alternative hydride sources revealed an unexpected substitution effect of the hydride source itself. The results presented confirm that the noncovalent combination of supramolecular hosts with iminium catalysis is opening up new exciting possibilities to increase enantioselectivity in challenging reactions.
Iminium Catalysis inside a Self-Assembled Supramolecular Capsule: Modulation of Enantiomeric Excess
Br?uer, Thomas M.,Zhang, Qi,Tiefenbacher, Konrad
, p. 7698 - 7701 (2016/07/07)
The noncovalent combination of a supramolecular host with iminium organocatalysis is described. Due to cation–π interactions the reactive iminium species is held inside the host and reacts in this confined environment. The products formed differ up to 92 % ee from the control experiments without added host. A model rationalizing the observed difference is presented.
Intermolecular enantioselective Heck-Matsuda arylations of acyclic olefins: Application to the synthesis of β-aryl-γ-lactones and β-aryl aldehydes
Oliveira, Caio C.,Angnes, Ricardo A.,Correia, Carlos Roque D.
, p. 4373 - 4385 (2013/06/27)
We describe herein a synthetically useful method for the enantioselective intermolecular Heck-Matsuda arylation of acyclic allylic alcohols. Aryldiazonium tetrafluoroborates were applied as arylating agents in the presence of Pd(TFA)2 and a chiral, commercially available, bisoxazoline ligand. The methodology is straightforward, robust, scalable up to a few grams, and of broad scope allowing the synthesis of a range of β-aryl-carbonyl compounds in good to high enantioselectivities and yields. This new enantioselective Heck-Matsuda arylation allowed the synthesis of β-aryl-γ-lactones and β-aryl aldehydes, which play a vital role as key intermediates in the synthesis of the biologically active compounds, such as (R)-baclofen, (R)-rolipram, (S)-curcumene, (S)-dehydrocurcumene, and (S)-tumerone.
Palladium/chiral amine co-catalyzed enantioselective β-arylation of α,β-unsaturated aldehydes
Ibrahem, Ismail,Ma, Guangning,Afewerki, Samson,C?rdova, Armando
supporting information, p. 878 - 882 (2013/02/23)
Palladium and a simple chiral amine are used as co-catalysts for the enantioselective conjugate addition of aryl boronic acids to α,β-unsaturated aldehydes (see scheme). The synthetic utility of this co-catalyzed reaction was demonstrated in the short tot
Total synthesis of (R)- and (S)-turmerone and (7S,9R)-bisacumol by an efficient chemoenzymatic approach
Kamal, Ahmed,Shaheer Malik,Azeeza, Shaik,Bajee, Shaik,Shaik, Ahmad Ali
experimental part, p. 1267 - 1271 (2009/10/17)
An enantioselective synthesis of (R)-, (S)-turmerone and (7S,9R)-bisacumol is described. The enantiomerically pure key intermediates, a substituted butanoate ester and acid are utilized in the synthesis of both enantiomers of turmerone. The lipase catalyzed resolution studies of the acetate of bisacumol have been exploited towards the total synthesis of the naturally occurring cytotoxic sesquiterpene, (7S,9R)-bisacumol with high diastereoselectivity (94% de).
Chiral benzyl centers through asymmetric catalysis. A three-step synthesis of (R)-(-)-α-curcumene via asymmetric hydrovinylation
Zhang, Aibin,RajanBabu
, p. 3159 - 3161 (2007/10/03)
(Chemical Equation Presented) A three-step, two-pot procedure involving asymmetric hydrovinylation followed by Suzuki-Miyaura reaction represents by far the shortest synthesis of this popular bisabolane. Other applications for the synthesis of similar com
Stereospecific Pd(0)-Catalyzed Arylation of an Allylic Hydroxy Phosphonate Derivative: Formal Synthesis of (S)-(+)-ar-Turmerone
Rowe, Bradley J.,Spilling, Christopher D.
, p. 9502 - 9505 (2007/10/03)
Reaction of the (1S)-allylic hydroxy phosphonate 1(S) with methyl chloroformate in pyridine yields the corresponding carbonate 3(S). The carbonate 3(S) undergoes a palladium-catalyzed arylation with p-tolyl tributylstannane to give both the 1E and 1Z viny
