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1.
Ek Raj Baral Yong Rok Lee Sung Hong Kim 《Advanced Synthesis \u0026amp; Catalysis》2015,357(13):2883-2892
The regioselective direct 3‐arylation of indoles with 1‐diazonaphthalen‐2‐(1H)‐ones was developed by means of a rhodium(II) pivalate‐catalyzed cross‐coupling reaction. This procedure provided a variety of novel 3‐naphthylindoles in high yield. The direct coupling of benzofuran, pyrrole or furan with 1‐diazonaphthalen‐2‐(1H)‐ones afforded 2‐ or 3‐naphthyl substituted heterocycles.
2.
Christoph K. Winkler Dorina Clay Nikolaus G. Turrini Horst Lechner Wolfgang Kroutil Simon Davies Sebastien Debarge Pat O'Neill Jeremy Steflik Mike Karmilowicz John W. Wong Kurt Faber 《Advanced Synthesis \u0026amp; Catalysis》2014,356(8):1878-1882
Asymmetric bioreduction of an (E)‐β‐cyano‐2,4‐dienoic acid derivative by ene‐reductases allowed a shortened access to a precursor of pregabalin [(S)‐3‐(aminomethyl)‐5‐methylhexanoic acid] possessing the desired configuration in up to 94% conversion and >99% ee. Deuterium labelling studies showed that the nitrile moiety was the preferred activating/anchor group in the active site of the enzyme over the carboxylic acid or the corresponding methyl ester.
3.
David Martin Vanessa M. Marx Robert H. Grubbs Guy Bertrand 《Advanced Synthesis \u0026amp; Catalysis》2016,358(6):965-969
A ruthenium complex bearing an “anti‐Bredt” N‐heterocyclic carbene was synthesized, characterized and evaluated as a catalyst for olefin metathesis. Good conversions were observed at room temperature for the formation of di‐ and tri‐substituted olefins by ring‐closing metathesis. It also allowed for the ring‐opening metathesis polymerization of cyclooctadiene, as well as for the cross‐metathesis of cis‐1,4‐diacetoxy‐2‐butene with allylbenzene, with enhanced Z/E kinetic selectivity over classical NHC‐based catalysts.
4.
Yangyang Chu Xiaoyu Hao Lili Lin Weiliang Chen Wei Li Fei Tan Xiaohua Liu Xiaoming Feng 《Advanced Synthesis \u0026amp; Catalysis》2014,356(10):2214-2218
The catalytic asymmetric epoxidation of 2‐arylidene‐1,3‐diketones using aqueous 30% H2O2 as oxidant has been successfully realized by a N,N′‐dioxide–scandium(III) triflate [Sc(OTf)3] complex, giving the corresponding products in moderate to good yields (up to 85%) with excellent enantioselectivities (up to 99% ee) under mild reaction conditions without extra additives.
5.
Siva Senthil Kumar Boominathan Wan‐Ping Hu Gopal Chandru Senadi Jeh‐Jeng Wang 《Advanced Synthesis \u0026amp; Catalysis》2013,355(18):3570-3574
A novel method has been developed for the synthesis of 3‐pyrrolines from β‐ketopropargylamines via a 5‐endo‐dig carbocyclization. This transformation involves a silver‐catalyzed Conia‐ene type reaction tolerating broad substrate scope with good to excellent yields. Furthermore, this methodology has been extended for the construction of 2‐substituted pyrroles under base‐mediated conditions.
6.
Multifunctional 3‐amino‐4‐dialkylphosphono‐2‐quinolinones have been prepared by “one‐pot” nucleophilic addition and regioselective ring enlargement of imino isatins. The addition reaction between imino isatins and dialkyl (diazomethyl)phosphonate proceeds smoothly using potassium carbonate as a catalyst, and a subsequent regioselective ring expansion promotes by salicylic acid to afford the desired products in high yields.
7.
Li Xing Zhoulong Fan Chengyu Hou Guoping Yong Ao Zhang 《Advanced Synthesis \u0026amp; Catalysis》2014,356(5):972-976
An efficient synthetic strategy for the unique class of pyrazolo[1,2‐a]cinnolines was developed through a rhodium‐catalyzed oxidative coupling of N‐aryl‐1H‐pyrazol‐5(4H)‐ones with internal alkynes. This protocol features use of the pyrazolone function in the substrate as an intrinsic directing group, hexafluoroisopropyl alcohol (HFIP) as the solvent, and mild reaction conditions as well as a wide substrate scope.
8.
Xiao‐Nan Zhang Gen‐Qiang Chen Xiang Dong Yin Wei Min Shi 《Advanced Synthesis \u0026amp; Catalysis》2013,355(17):3351-3357
A novel asymmetric [4+2] annulation of vinyl ketones with oxindole‐derived α,β‐unsaturated imines has been developed in the presence of a multifunctional thiourea‐phosphine catalyst derived from a natural amino acid, providing the first phosphine‐catalyzed enantioselective synthesis of 2′,3′‐dihydro‐1′H‐spiro[indoline‐3,4′‐pyridin]‐2‐ones in good yields with excellent stereoselectivities under mild conditions.
9.
The asymmetric aldol reaction of 3‐acetyl‐2H‐chromen‐2‐ones and isatins has been realized by using a bifunctional quinidine‐derived urea as the catalyst. The corresponding 3‐hydroxyoxindole derivatives containing a 2H‐chromen‐2‐one moiety were obtained in good yields and high enantioselectivities. When (Z)‐ethyl 2‐benzylideneacetoacetate was used as the substrate, a mixture of two diastereomers (both Z and E) was obtained due to isomerization of the double bond under the reaction conditions.
10.
Qiang Wang Zhong Lian Qin Xu Min Shi 《Advanced Synthesis \u0026amp; Catalysis》2013,355(17):3344-3350
The catalytic asymmetric [4+2] annulations of isatins with but‐3‐yn‐2‐one catalyzed by the Cinchona alkaloids‐derived oragnocatalyst (DHQD)2PHAL have been developed in the presence of 3.0 equivalents of D ‐diethyl tartrate in the mixed solvent (diphenyl ether/diethyl ether=1/1) or a slightly modified one, affording the corresponding substituted spiro[indoline‐3,2′‐pyran]‐2,4′(3′H)‐diones in good to excellent yields with high enantioselectivities under mild conditions.
11.
Yakun Wang Hang Yin Hai Qing Jingnan Zhao Yufeng Wu Qingwei Meng 《Advanced Synthesis \u0026amp; Catalysis》2016,358(5):737-745
The highly catalytic asymmetric α‐hydroxylation of β‐indanone esters and β‐indanone amides using peroxide as the oxidant was realized with a new C‐2′ substituted Cinchona alkaloid derivatives. The two enantiomers of α‐hydroxy‐β‐indanone esters could be obtained by simply changing the oxidant. This protocol allows a convenient access to the corresponding α‐hydroxy‐β‐indanone esters and α‐hydroxy‐β‐indanone amides with up to 99% yield and 98% ee.
12.
Antonino Ferraro Luca Bernardi Mariafrancesca Fochi 《Advanced Synthesis \u0026amp; Catalysis》2016,358(10):1561-1565
The asymmetric organocatalytic transfer hydrogenation of β‐acylamino and β‐tert‐butyloxycarbonylamino nitroolefins has been successfully realised in excellent enantioselectivities and yields (up to >99% ee, 97% yield) with a simple thiourea catalyst and a Hantzsch ester as hydrogen source, giving a direct access to enantiomerically pure β‐amino nitroalkanes.
13.
Mei Xu Tian‐Tian Ren Kai‐Bing Wang Chuan‐Ying Li 《Advanced Synthesis \u0026amp; Catalysis》2013,355(13):2488-2494
In the presence of a gold catalyst and 8‐ethylquinoline N‐oxide, a homopropargylic ether bearing an electron‐rich aromatic ring or an alkenyl group can be converted into a cis‐cyclobutanone smoothly. An α‐oxo gold carbenoid is proved to be the key intermediate, and it can evolve into an oxonium ylide.
14.
Ko Hoon Kim Jin Woo Lim Junseung Lee Min Jeong Go Jae Nyoung Kim 《Advanced Synthesis \u0026amp; Catalysis》2014,356(16):3363-3369
Various 3‐azabicyclo[3.1.1]heptane derivatives were synthesized from Morita–Baylis–Hillman adduct‐derived 1,3‐dienes bearing a 4,4‐diaryl moiety through a thermal intramolecular [2+2] cycloaddition approach. By using the same approach, bicyclo[3.1.1]heptane, 3‐azabicyclo[3.2.0]heptane, and 3‐oxabicyclo[3.1.1]heptane derivatives could also be synthesized. A structurally similar dimethylallyl derivative underwent an intramolecular ene reaction to afford the pyrrolidine derivative.
15.
You‐Qing Wang Yongna Zhang Kun Pan Junxiong You Jin Zhao 《Advanced Synthesis \u0026amp; Catalysis》2013,355(17):3381-3386
3‐Substituted‐2H‐1,4‐benzoxazines undergo a highly enantioselective direct Mannich reaction with acetone in the presence of an L ‐proline catalyst at room temperature. The corresponding N‐heterocycles with α‐tetrasubstituted carbon stereocenters were obtained in good yields (48–92%) and excellent enantioselectivity (up to >99% ee). Furthermore, a novel modification involving the diastereoselective reduction of the Mannich adduct was carried out leading to the formation of a 1,3‐amino alcohol with a chiral tetrasubstituted carbon stereocenter in high yield.
16.
Rafa Kowalczyk Przemysaw J. Boratyski 《Advanced Synthesis \u0026amp; Catalysis》2016,358(8):1289-1295
Organocatalyzed highly stereoselective 1,4‐thia‐Michael addition of mercaptans to linear 2,4‐dienones and 2‐en‐4‐ynones was developed using Cinchona alkaloid‐based squaramides. Application of only 0.5–1 mol % loading afforded products in up to 98:2 e.r. and above 99:1 after a single recrystallization. The adducts of allyl mercaptan can be conveniently further transformed to new chiral 2‐substituted 2,5‐dihydrothiophenes by ring‐closing metathesis.
17.
Beatriz C. Calvo Ashoka V. R. Madduri Syuzanna R. Harutyunyan Adriaan J. Minnaard 《Advanced Synthesis \u0026amp; Catalysis》2014,356(9):2061-2069
The copper/Rev‐JosiPhos‐catalysed asymmetric conjugate addition of Grignard reagents to 2‐methylcyclopentenone ( 1 ) provides 2,3‐disubstituted cyclopentanones in high yields and enantioselectivities, and good diastereoselectivities. Reaction of the in situ formed enolate with various alkylating reagents in the presence of 1,3‐dimethyltetrahydropyrimidine‐2(1H)‐one (DMPU) affords the corresponding products in a one‐pot reaction. This procedure creates two vicinal stereocentres, one of them quaternary.
18.
Melireth Holmquist Gonzalo Blay M. Carmen Muoz Jos R. Pedro 《Advanced Synthesis \u0026amp; Catalysis》2015,357(18):3857-3862
A new enantioselective route to spiro[piperidine‐3,3′‐oxindoles] from isatin ketimines is described. The aza‐Henry reaction of N‐Boc‐isatin ketimines with methyl 4‐nitrobutyrate in the presence of a Ph2BOX‐CuBr2 complex provided the corresponding nitro amino esters with good diastereoselectivity and excellent enantioselectivity (up to >99% ee). The aza‐Henry adducts were transformed into spiro[piperidine‐3,3′‐oxindoles] after reduction of the nitro group to oxime, and cleavage of the N‐Boc group and lactamisation.
19.
Woo‐Soon Yong Sangjune Park Hyunsik Yun Phil Ho Lee 《Advanced Synthesis \u0026amp; Catalysis》2016,358(12):1958-1967
A synthetic method to prepare a wide range of 2H‐indazoles was developed via a tandem palladium‐catalyzed deacylative cross‐coupling reaction of 2‐iodoazoarenes and 2‐iodoaryltriazenes with acyldiazoacetates and denitrogenative cyclization reaction of in situ generated diazoacetates having azoaryl and triazenylaryl moieties in one‐pot. Additionally, azoaryl‐substituted diazoacetates underwent palladium‐catalyzed denitrogenative cyclization to produce 2H‐indazoles. The present reaction is a good example in which a Pd(0)‐catalyst is involved in two catalytic cycles in one‐pot.
20.
Ziwei Hu Jian Wang Dongdong Liang Qiang Zhu 《Advanced Synthesis \u0026amp; Catalysis》2013,355(16):3290-3294
A three‐component reaction involving isocyanides, o‐alkynyltrifluoroacetanilides, and amines for the efficient synthesis of 2‐substituted 1H‐indole‐3‐carboxamidines has been developed. The reaction proceeds through intramolecular aminopalladation of alkynes activated by isocyanide‐ligated palladium(II) species. Dioxygen acts as the sole oxidant to regenerate the active palladium(II) species.