- Organocatalytic Regio- and Enantioselective N-Alkylation of Isoxazol-5-ones
-
A chiral phosphoric acid catalyzed regio- and enantioselective reaction between 1-acylamino-3-arylprop-2-yn-1-ols and isoxazol-5-ones has been developed for the first time. With the established protocol, N-alkylation of isoxazol-5-ones was achieved, affording enantioenriched N,N-acetals in 74–99 % yield with 72–88 % ee.
- Li, Pengfei,Liu, Meiwen,Qian, Chenxiao
-
supporting information
p. 6777 - 6780
(2021/12/31)
-
- Synthesis of Azepino[1,2-a]indole-10-amines via [6+1] Annulation of Ynenitriles with Reformatsky Reagent
-
Lewis acid-catalyzed [6+1] annulation reactions of 2-cyano-1-propargyl- and 2-alkynyl-1-cyanomethyl-indoles with Reformatsky reagent are described. 8-Aryl, 8-alkyl-, 8-hetaryl-, 9-aryl, and 9-alkyl-azepino[1,2-a]indole amines were obtained through a 7-endo-mode cyclization of the β-aminoacrylate intermediates. The antiproliferative activity of the azepino[1,2-a]indoles analogs against the HCT-116 cells were also examined.
- Iioka, Ryoya,Yorozu, Kohei,Sakai, Yoko,Kawai, Rika,Hatae, Noriyuki,Takashima, Katsuki,Tanabe, Genzoh,Wasada, Hiroaki,Yoshimatsu, Mitsuhiro
-
supporting information
p. 1553 - 1558
(2021/02/26)
-
- Transition-metal-free and facile synthesis of 3-alkynylpyrrole-2,4-dicarboxylates from methylene isocyanides and propiolaldehyde
-
A transition-metal-free, facile and efficient method for the synthesis of 3-alkynylpyrrole-2,4-dicarboxylates from methylene isocyanides and propiolaldehyde with moderate to good yields has been developed. The direct transformation process and good tolerance of various substituents make it an alternative approach to previous protocols, and potential applications of these investigated compounds are expected with or without post-modifications.
- Chen, Xiaojuan,Fu, Liping,Huo, Xiaoli,Shao, Jiaan,Yu, Liya,Zeng, Linghui,Zhang, Chong,Zhang, Jiankang,Zhu, Huajian
-
supporting information
p. 16430 - 16433
(2021/10/01)
-
- Chemoselective Hydroboration of Propargylic Alcohols and Amines Using a Manganese(II) Catalyst
-
The first manganese-catalyzed hydroboration of propargylic alcohols and amines as well as internal alkynes is reported. High regio- and stereoselectivity is achieved by applying 2 mol % of a manganese precatalyst based on the readily accessible bis(imino)pyridine ligand and MnCl2 as metal source. Propargylic alcohols and amines, as well as symmetric internal alkynes, were efficiently converted into the corresponding functionalized alkenes, which can serve as important and valuable intermediates for further synthetic applications such as cross-coupling reactions.
- Brzozowska, Aleksandra,Zubar, Viktoriia,Ganardi, Ruth-Christine,Rueping, Magnus
-
supporting information
p. 3765 - 3769
(2020/04/15)
-
- Applications of Thermal Activation, Ball-milling and Aqueous Medium in Stereoselective Michael Addition of Nitromethane to Enynones Catalyzed by Chiral Squaramides
-
Stereoselective addition of nitromethane to conjugated en-ynones was performed through the application of chiral squaramides. Three non-classical approaches to promote the addition reaction were tested, including activation of the nucleophile by inorganic base in a biphasic aqueous system, thermal activation, and ball-milling. Hydrogen-bonding catalysis was effective in all these methods, providing 1,4-addition products in high yields and stereoselectivities of up to 98% requiring 1–5 mol% of Cinchona alkaloid squaramide. (Figure presented.).
- Ignatiuk, ?aneta A.,Janicki, Miko?aj J.,Góra, Robert W.,Konieczny, Krzysztof,Kowalczyk, Rafa?
-
supporting information
p. 1108 - 1116
(2019/01/30)
-
- Nickel(II)-Catalyzed Asymmetric Propargyl [2,3] Wittig Rearrangement of Oxindole Derivatives: A Chiral Amplification Effect
-
A highly enantioselective [2,3] Wittig rearrangement of oxindole derivatives was realized by using a chiral N,N′-dioxide/NiII complex as the catalyst under mild reaction conditions. A strong chiral amplification effect was observed, and allowed access to chiral 3-hydroxy 3-substituted oxindoles bearing allenyl groups in high yields and enantioselectivities (up to 92 % ee) by using a ligand with only 15 % ee. A reasonable explanation was given based on the experimental investigations and X-ray crystal structures of enantiomerically pure and racemic catalysts. Moreover, the first catalytic kinetic resolution of racemic oxindole derivatives by a [2,3] Wittig rearrangement was realized with high efficiency and stereoselectivity.
- Xu, Xi,Zhang, Jianlin,Dong, Shunxi,Lin, Lili,Lin, Xiaobin,Liu, Xiaohua,Feng, Xiaoming
-
supporting information
p. 8734 - 8738
(2018/07/14)
-
- Gold(I)-Initiated Cycloisomerization/Diels-Alder/Retro-Diels-Alder Cascade Strategy to Biaryls
-
A unique approach to biaryls was developed on the basis of propargyl vinyl ethers and dienophiles substrates via a gold(I)-initiated cycloisomerization/Diels-Alder/retro-Diels-Alder cascade reaction. The scope and mechanism of the reaction were investigated on the basis of a series of synthetic substrates, control experiments, and DFT calculations.
- Jin, Shengfei,Niu, Yujie,Liu, Chengjun,Zhu, Lifeng,Li, Yangming,Cui, Shanshan,Xiong, Zhiling,Cheng, Maosheng,Lin, Bin,Liu, Yongxiang
-
p. 9066 - 9074
(2017/09/11)
-
- Facile synthesis of substituted 3-aminofurans through a tandem reaction of N-sulfonyl-1,2,3-triazoles with propargyl alcohols
-
A relay catalysis strategy for substituted 3-aminofurans synthesis has been developed. This transformation involves a tandem reaction sequence through aza-vinyl-rhodium(ii) carbene O-H bond insertion, thermal propargyl-Claisen rearrangement and gold(i)-catalyzed intramolecular cyclization. More importantly, the current strategy employs simple feedstocks as starting materials, providing substituted 3-aminofurans in a highly efficient manner.
- Cheng, Xing,Yu, Yinghua,Mao, Zhifeng,Chen, Jianxin,Huang, Xueliang
-
supporting information
p. 3878 - 3882
(2016/06/01)
-
- Zinc-catalyzed [4+3] cycloaddition with concomitant furan annulation: Formation of cyclohepta[b]furans
-
A convenient zinc-promoted [4+3] cycloaddition of a carbonyl ene-yne with simple dienes was first achieved. This reaction provided an efficient strategy to prepare various cyclohepta[b]furan rings by cascade cycloadditions. Additionally, a multicomponent reaction of dione, alkynal, and diene was also reported, which exhibited a novel strategy for selective creations of C-O bonds and C-C bonds. Go tandem! A first zinc-catalyzed tandem [4+3] cycloaddition is presented herein. Various substituted cyclohepta[b]furans were synthesized from carbonyl ene-yne and diene in moderate to good yield. Furan rings and seven-membered rings were prepared in one single step (see scheme; TBS=tert-butyldimethyl).
- Song, Bo,Li, Lian-Hua,Song, Xian-Rong,Qiu, Yi-Feng,Zhong, Mei-Jin,Zhou, Ping-Xin,Liang, Yong-Min
-
supporting information
p. 5910 - 5913
(2014/05/20)
-
- Lactone radical cyclizations and cyclization cascades mediated by SmI 2-H2O
-
Unsaturated lactones undergo reductive radical cyclizations upon treatment with SmI2-H2O to give decorated cycloheptanes in a single highly selective operation during which up to three contiguous stereocenters are generated. Furthermore, cascade processes involving lactones bearing two alkenes, an alkene and an alkyne, or an allene and an alkene allow "one-pot" access to biologically significant molecular scaffolds with the construction of up to four contiguous stereocenters. The cyclizations proceed by the trapping of radical anions formed by electron transfer reduction of the lactone carbonyl.
- Parmar, Dixit,Matsubara, Hiroshi,Price, Kieran,Spain, Malcolm,Procter, David J.
-
supporting information; experimental part
p. 12751 - 12757
(2012/09/05)
-
- Gold-catalyzed annulation/fragmentation: Formation of free gold carbenes by retro-cyclopropanation
-
The gold(I)-catalyzed cyclization of 1-(prop-2-yn-1-yl)-2-alkenylbenzenes substituted at the benzylic position with OR groups gives 1,3-disubstituted naphthalenes with concomitant fragmentation of the alkene. One of these annulations proceeds by a retro-cyclopropanation that leads to free gold(I) carbenes.
- Solorio-Alvarado, Cesar R.,Echavarren, Antonio M.
-
supporting information; experimental part
p. 11881 - 11883
(2010/10/19)
-
- 1-(1,2,5-thiadiazol-4-yl)-4-azatricyclo[2.2.1.02,6]heptanes as new potent muscarinic M1 agonists: Structure-activity relationship for 3-aryl- 2-propyn-1-yloxy and 3-aryl-2-propyn-1-ylthio derivatives
-
Two new series of 1-(1,2,5-thiadiazol-4-yl)-4- azatricyclo[2.2.1.02,6]heptanes were synthesized and evaluated for their in vitro activity in cell lines transfected with either the human M1 or M2 receptor. 3-Phenyl-2-propyn-1-yloxy and -1-ylthio analogues substituted with halogen in the meta position showed high functional potency, efficacy, and selectivity toward the M1 receptor subtype. A quite unique functional M1 receptor selectivity was observed for compounds 8b, 8d, 8f, 9b, 9d, and 9f. Bioavailability studies in rats indicated an oral bioavailability of about 20-30%, with the N-oxide as the only detected metabolite.
- Jeppesen, Lone,Olesen, Preben H.,Hansen, Lena,Sheardown, Malcolm J.,Thomsen, Christian,Rasmussen, Th?ger,Jensen, Anders Fink,Christensen, Michael S.,Rimvall, Karin,Ward, John S.,Whitesitt, Celia,Calligaro, David O.,Bymaster, Frank P.,Delapp, Neil W.,Felder, Christian C.,Shannon, Harlan E.,Sauerberg, Per
-
p. 1999 - 2006
(2007/10/03)
-
- Design and synthesis of m1-selective muscarinic agonists: (R)-(-)-(Z)- 1-azabicyclo[2.2.1]heptan-3-one, O-(3-(3'-methoxyphenyl)-2-propynyl)-oxime maleate (CI-1017), a functionally m1-selective muscarinic agonist
-
The synthesis and SAR of a series of (Z)-(±)-1- azabicyclo[2.2.1]heptan-3-one, O-(3-aryl-2-propynyl)oximes are described. The biochemistry and pharmacology of 24Z (PD 142505) and its enantiomers are highlighted. 24Z is functionally an m1-selective muscari
- Tecle, Halle,Barrett, Stephen D.,Lauffer, David J.,Augelli-Szafran, Corinne,Brann, Mark R.,Callahan, Michael J.,Caprathe, Bradley W.,Davis, Robert E.,Doyle, Patricia D.,Eubanks, David,Lipiniski, William,Mirzadegan, Tara,Moos, Walter H.,Moreland,Nelson, Carrie B.,Pavia, Michael R.,Raby, Charlotte,Schwarz, Roy D.,Spencer, Carolyn J.,Thomas, Anthony J.,Jaen, Juan C.
-
p. 2524 - 2536
(2007/10/03)
-
- Novel 5-(3-aryl-2-propynyl)-5-(arylsulfonyl)thiazolidine-2,4-diones as antihyperglycemic agents
-
Novel 5-(3-aryl-2-propynyl)-5-(arylsulfonyl)thiazolidine-2,4-diones and 5-(3-aryl-2-propynyl)5-(arylsulfanyl)thiazolidine-2,4-diones were prepared and evaluated as oral antihyperglycemic agents in the obese, insulin resistant db/db mouse model at 100 mg/kg and, if the analogue had sufficient potency, 20 mg/kg. The sulfonylthiazolidinediones, 2, were more potent than the corresponding sulfanylthiazolidinedione congeners, 1. With regard to substituent effects on the 3-propynyl phenyl ring (Ar') of 2, 4-halogen substitution generally resulted in the more potent analogues. Substituent effects on the phenylsulfonyl moiety (Ar) of 2 were less clear, although para-halogen substitution on Ar generally was preferable. 2-Pyridinesulfonyl derivatives (Ar = 2-pyridine in 2) also had good potency. Several compounds from series 2 were effective at lowering glucose and insulin in the obese, insulin resistant ob/ob mouse at the 50 mg/kg oral dose. Compound 20 significantly improved the glucose tolerance of obese, insulin resistant Zucker rats at the 20 mg/kg dose level and had no effect on plasma glucose or on glucose tolerance in normal rats fasted for 18 h at the 100 mg/kg level.
- Wrobel, Jay,Li, Zenan,Dietrich, Arlene,McCaleb, Michael,Mihan, Brenda,Sredy, Janet,Sullivan, Donald
-
p. 1084 - 1091
(2007/10/03)
-
- Cyclopropanecarboxylic acid alkynyl esters, processes for producing them, and their use as pesticides
-
Cyclopropanecarboxylic acid alkynyl esters of the formula I STR1 wherein R1 is unsubstituted or substituted phenyl or thienyl, R2 is hydrogen, alkyl having 1-6 C atoms, alkenyl having 2-6 C atoms, or phenyl or naphthyl which is unsubstituted or substituted by an alkyl or alkoxy group having 1-2 C atoms or by a halogen atom, and R3 is hydrogen, alkyl having 1-6 C atoms or alkenyl having 2-6 C atoms, are suitable for combating various plant and animal pests, particularly insects, and members of the order Acarina. They can be obtained by reaction of corresponding alkynols with cyclopropanecarboxylic acid or with a reactive functional derivative thereof.
- -
-
-