- Flexible Construction of Functionalized-Pyrroles under Palladium or Copper Catalysis in the Presence of BF3 ? Et2O
-
We have developed a flexible approach enabling the access to highly functionalized pyrroles under palladium or copper catalysis in the presence of BF3 ? Et2O. This catalytic methodology utilizes commercially available amines as react
- Guo, Wusheng,Liu, Teng,Liu, Yin,Wei, Kun,Yan, Biwei
-
supporting information
(2022/01/26)
-
- 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
-
p. 16430 - 16433
(2021/10/01)
-
- NHC-catalyzed enantioselective C2-functionalization of 3-hydroxychromenonesviaα,β-unsaturated acyl azoliums
-
A novel synthetic method for enantioselective C2-functionalization of 3-hydroxychromenones promoted by N-heterocyclic carbenesviathe formation of α,β-unsaturated acyl azolium intermediates, which occurs with Coates-Claisen rearrangement is established. This synthetic strategy enabled the rapid assembly of enantiomerically enriched δ-hydroxychromenone-derived esters/amides under mild conditions with good to excellent yields and broad substrate scope.
- Dzieszkowski, Krzysztof,S?otwiński, Micha?,Rafińska, Katarzyna,Muzio?, Tadeusz M.,Rafiński, Zbigniew
-
supporting information
p. 9999 - 10002
(2021/10/06)
-
- Micelle-Mediated Trimerization of Ynals to Orthogonally Substituted 4H-Pyrans in Water: Downstream Rearrangement to Bioactive 2,8-dioxabicyclo[3.3.1]nona-3,6-diene Frameworks
-
An efficient trimerization of ynals to diversely substituted 4H-pyran constructs has been executed in water, under ambient conditions employing micellar catalysis. The method is in agreement with the ideas of green and sustainable chemistry. The locus of the micellar reaction site has been probed through proton NMR studies. A general acid-mediated downstream rearrangement of the derived 4H-pyrans to interesting 2,8-dioxabicyclo[3.3.1]nona-3,6-dienes has been observed.
- Rashid, Showkat,Bhat, Bilal A.,Mehta, Goverdhan
-
supporting information
p. 6646 - 6651
(2021/10/14)
-
- Synthesis of Chiral Propargylamines, Chiral 1,2-Dihydronaphtho[2,1-b]furans and Naphtho[2,1-b]furans with C-Alkynyl N,N′-di-(tert-butoxycarbonyl)-aminals and β-Naphthols
-
Chiral phosphoric acid-catalyzed couplings of C-alkynyl N,N′-di-(tert-butoxycarbonyl)-aminals with β-naphthols led to chiral propargylamines in moderate to high yields with high to excellent enantioselectivity, in which the reactions underwent sequential chiral phosphoric acid-catalyzed in situ formation of N-(tert-butoxycarbonyl)-imines (N-Boc-imines) from the aminals, and 1,2-addition of β-naphthols to the N-Boc-imines. Chiral 1,2-dihydronaphtho[2,1-b]furans and naphtho[2,1-b]furans were prepared with satisfactory results when 10 mol% AgOAc and 20 mol% 2,6-lutidine or 1.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) were added to the resulting chiral propargylamines solution, respectively.
- Man, Ningning,Li, Yuming,Jie, Jiyang,Li, Hongyun,Yang, Haijun,Zhao, Yufen,Fu, Hua
-
supporting information
p. 12884 - 12889
(2021/07/28)
-
- RET INHIBITORS, PHARMACEUTICAL COMPOSITIONS AND USES THEREOF
-
Provided herein are a RET inhibitor, a pharmaceutical composition thereof and uses thereof. In particular, provided is a compound having Formula (I) or a stereoisomer, a geometric isomer, a tautomer, an N-oxide, a solvate, a metabolite, a pharmaceutically acceptable salt or a prodrug thereof. Provided is a pharmaceutical composition comprising the compound, and uses of the compound and pharmaceutical composition thereof for the preparation of a medicament, in particular for treatment and prevention of RET-related diseases and conditions, including cancer, irritable bowel syndrome, and/or pain associated with irritable bowel syndrome.
- -
-
-
- RET INHIBITORS, PHARMACEUTICAL COMPOSITIONS AND USES THEREOF
-
Provided herein are a RET inhibitor, a pharmaceutical composition thereof and uses thereof. In particular, provided is a compound having Formula (I) or a stereoisomer, a geometric isomer, a tautomer, an N-oxide, a solvate, a metabolite, a pharmaceutically acceptable salt or a prodrug thereof. Provided is a pharmaceutical composition comprising the compound, and uses of the compound and pharmaceutical composition thereof for the preparation of a medicament, in particular for treatment and prevention of RET-related diseases and conditions, including cancer, irritable bowel syndrome, and/or pain associated with irritable bowel syndrome.
- -
-
-
- Regiodivergent Hydration-Cyclization of Diynones under Gold Catalysis
-
Skipped diynones, efficiently prepared from biomass-derived ethyl lactate, undergo a tandem hydration-oxacyclization reaction under gold(I) catalysis. Reaction conditions have been developed for a switchable process that allows selective access to 4-pyrones or 3(2H)-furanones from the same starting diynones. Further application of this methodology in the total synthesis of polyporapyranone B was demonstrated.
- Mu?oz, Miguel A.,Sanz, Roberto,Solas, Marta,Suárez-Pantiga, Samuel
-
supporting information
p. 7681 - 7687
(2020/10/12)
-
- Catalyst-Free Annulation of 2-Pyridylacetates and Ynals with Molecular Oxygen: An Access to 3-Acylated Indolizines
-
A catalyst and additive-free annulation of 2-pyridylacetates and ynals under molecular oxygen was the first developed, affording 3-acylated indolizines in good to excellent yields. Molecular oxygen was used as the source of the carbonyl oxygen atom in indolizines. This approach was compatible with a wide range of functional groups, and especially it has been successfully extended to unsaturated double bonds and triple bonds, which were difficult to prepare by previous methods in a single step.
- Chen, Zhengwang,Liang, Pei,Ma, Xiaoyue,Luo, Haiqing,Xu, Guohai,Liu, Tanggao,Wen, Xiaowei,Zheng, Jing,Ye, Hui
-
p. 1630 - 1639
(2019/01/26)
-
- Rhodium-Catalyzed 1,1-Hydroacylation of Thioacyl Carbenes with Alkynyl Aldehydes and Subsequent Cyclization
-
A rhodium-catalyzed 1,1-hydroacylation of thioacyl carbenes with alkynyl and alkenyl aldehydes and subsequent 6-endo-trig/dig cyclization are realized, giving structurally diverse 4H-thiopyran-4-ones and 2,3-dihydro-4H-thiopyran-4-ones in moderate to good yields. The oxidative addition of Rh(I) to aldehydes is proposed to be the turnover-limiting step. Manipulations of estrones demonstrate the applications of our formal (3 + 3) transannulations in the structural modifications of natural products.
- Zhou, Bingnan,Wu, Qiuyue,Dong, Ziyang,Xu, Jiaxi,Yang, Zhanhui
-
p. 3594 - 3599
(2019/05/24)
-
- Iron-Catalyzed Aerobic Oxidation of Alcohols: Lower Cost and Improved Selectivity
-
An aerobic oxidation reaction of alcohols toward aldehydes or ketones using catalytic amounts of Fe(NO3)3·9H2O, 4-OH-TEMPO, and NaCl has been developed. Compared with the former catalytic system with TEMPO developed in this group, the new protocol using 4-OH-TEMPO, which is much cheaper on an industrial scale, accomplished the transformation with a higher selectivity, especially for aliphatic alcohols toward aldehydes. α,β-Unsaturated alkynals or alkynones can be efficiently synthesized from propargyl alcohols, which has been much less studied in the literature.
- Jiang, Xingguo,Liu, Jinxian,Ma, Shengming
-
p. 825 - 835
(2019/05/02)
-
- Gold-Catalyzed Synthesis of 2,5-Disubstituted Oxazoles from Carboxamides and Propynals
-
2,5-Disubstituted oxazoles are synthesized by oxidative gold catalysis. In contrast to a reported procedure that delivers 2,4-disubstituted oxazoles starting from terminal alkynes, a switch in selectivity towards a 2,5-disubstitution is achieved by the use of propynals as starting materials. In the new reaction, the key intermediate is formed by the nucleophilic attack of the carboxamide onto a gold carbenoid, and then condensates with the more electrophilic aldehyde moiety already present in the substrate and not with the ketone that is derived from the oxygen donor. This new cyclization mode introduces a new carbonyl moiety as substituent at the 2,5-disubstituted oxazole, an attractive motive that can be found in bioactive compounds or be used for further derivatizations. (Figure presented.).
- Xu, Yun,Wang, Qian,Wu, Yufeng,Zeng, Zhongyi,Rudolph, Matthias,Hashmi, A. Stephen K.
-
supporting information
p. 2309 - 2314
(2019/04/13)
-
- Regioselective Synthesis of Indene from 3-Aryl Propargylic gem-Dipivalates Catalyzed by N-Heterocyclic Carbene Gold(I) Complexes
-
1-Aryl-3,3-bis(pivaloyloxy)propynes can be converted in good to high yields into either 1,3- or 1,2-bis(pivaloyloxy)indenes, depending on the N-heterocyclic carbene (NHC) gold(I) hexafluoroantimonate catalyst used. Almost exclusive formation of 1,3-di(oxycarbonyl)indene derivatives was achieved with cationic gold complexes containing the embracing N,N′-1,3-bis(9-butylfluorenyl)benzimidazolylidene ligand (nBuFNHC). The regioselective issue of the reaction was rationalized by the specific spatial distribution of the steric bulk in the nBuFNHC ligand. In contrast, only modest selectivities in favor of 1,2-disubstituted indenes were observed with more classical NHC gold complexes, the best selectivity being then obtained with N,N′-1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazolylidene gold chloride (SIPrAuCl) as precatalyst. (Figure presented.).
- Hueber, Damien,Teci, Matthieu,Brenner, Eric,Matt, Dominique,Weibel, Jean-Marc,Pale, Patrick,Blanc, Aurélien
-
p. 2453 - 2459
(2018/05/14)
-
- Base-Promoted Tandem Cyclization for the Synthesis of Benzonitriles by C?C Bond Construction
-
A facile synthesis of benzonitriles via a base-promoted tandem cyclization reaction of α,β-unsaturated enones having electron-withdrawing group (EWG) and 2-acyl-acrylonitriles was developed. This new synthetic method to access benzonitriles is suitable for a wide range of substrates. A plausible reaction mechanism is proposed on the basis of previous literature and our own investigations. (Figure presented.).
- Zhu, Cheng-Zhi,Wei, Yin,Shi, Min
-
supporting information
p. 808 - 813
(2018/01/27)
-
- Gold-Catalyzed [4 + 1]-Annulation Reactions between 1,4-Diyn-3-ols and Isoxazoles to Construct a Pyrrole Core
-
This work reports gold-catalyzed [4 + 1]-annulation reactions between 1,4-diyn-3-ols and isoxazoles or benzisoxazoles to yield pyrrole derivatives. The reaction chemoselectivity is controlled by an initial attack of an isoxazole at a less hindered alkyne to form gold carbenes, further inducing a 1,2-migration of a second alkyne group. A broad substrate scope of 1,4-diyn-3-ols, isoxazoles and even benzisoxazoles highlighted the reaction utility.
- Kardile, Rahul Dadabhau,Kale, Balaji S.,Sharma, Pankaj,Liu, Rai-Shung
-
supporting information
p. 3806 - 3809
(2018/07/25)
-
- Two-Step Synthesis of (Z)-3-Aryl-5-(arylmethylidene)butenolides by an Ivanov Reaction/Silver(I)-Catalyzed Lactonization/In Situ Dehydration Sequence
-
A stereoselective synthesis of the title compounds was developed. Hexane- and amine-free THF solutions of α-lithiated lithium arylacetates ('arylacetic acid dianions') were aldol-added to 3-arylpropynals. This gave 2,5-diaryl-3-hydroxypent-4-ynoic acids with up to a 72:28 preference for the anti-diastereomer (27 examples + 1 exception). When treated with Ag2CO3 (1-20 mol%) in DMF at room temperature for 2.5 days, the respective mixtures underwent regio- and stereoselective lactonizations followed by an in situ dehydration. Thereby 3-aryl-5-(arylmethylidene)butenolides were obtained with a Z-configuration of the oxygenated C=C bond. Their overall yields ranged from 46% to 83% (1 exception: 28%). Three 3-aryl-5-(arylmethylidene)butenolides contained a C-Br and/or a C-I bond. They allowed a subsequent Pd-catalyzed C-C coupling, which furnished follow-up butenolides.
- Hermann, David,Arican, Deniz,Brückner, Reinhard
-
p. 326 - 352
(2016/12/24)
-
- [4+2] or [4+1] Annulation: Changing the Reaction Pathway of a Rhodium-Catalyzed Process by Tuning the Cp Ligand
-
A change in reaction pathway was achieved for the first time by tuning the cyclopentadienyl (Cp) ligand used for the rhodium-catalyzed cyclization of benzamides with conjugated enynones. Depending on the Cp ligand, the reaction pathway switched between [4+2] and [4+1] annulation. Electronic effects turned out to be crucial for the product distribution. The dichotomy was attributed to the alteration of the Lewis acidity of the resultant Cp-bound rhodium species.
- Hong, Seung Youn,Jeong, Jisu,Chang, Sukbok
-
supporting information
p. 2408 - 2412
(2017/02/23)
-
- Phosphine-Mediated Dimerization of Conjugated Ene-Yne Ketones: Stereoselective Construction of Dihydrobenzofurans
-
A new strategy for the phosphine-mediated dimerization of conjugated ene-yne ketones to produce functionalized dihydrobenzofurans has been developed, affording diversified 4,5-dihydrobenzofurans in moderate to excellent yields with high diastereoselectivities under mild conditions. This new synthetic method can tolerate a variety of functional groups and can be performed on a gram scale and in an asymmetric variant using the chiral phosphine Xyl-BINAP to give the desired products with up to 94% ee. (Figure presented.).
- Zhu, Cheng-Zhi,Sun, Yao-Liang,Wei, Yin,Shi, Min
-
supporting information
p. 1263 - 1270
(2017/04/18)
-
- Catalytic Enantioselective Synthesis of Amino Skipped Diynes
-
The Cu-catalyzed synthesis of nonracemic 3-amino skipped diynes via an enantiodetermining C-C bond formation is described using StackPhos as ligand. Despite challenging issues of reactivity and stereoselectivity inherent to these chiral skipped diynes, the reaction tolerates an extremely broad substrate scope with respect to all components and provides the title compounds in excellent enantiomeric excess. The alkyne moieties are demonstrated here to be useful synthetic handles, and 3-amino skipped diynes are convenient building blocks for enantioselective synthesis.
- Paioti, Paulo H. S.,Abboud, Khalil A.,Aponick, Aaron
-
p. 2150 - 2153
(2016/03/05)
-
- (E)-2-(4-Arylbut-1-en-3-yn-1-yl)chromones as Synthons for the Synthesis of Xanthone-1,2,3-triazole Dyads
-
Xanthone-1,2,3-triazole dyads have been synthesized by two different approaches, both starting from novel (E)-2-(4-arylbut-1-en-3-yn-1-yl)chromones, prepared through a base-catalyzed aldol reaction of 2-methylchromone and arylpropargyl aldehydes. In the first method, the xanthone moiety is built by Diels-Alder reaction of the referred unsaturated chromones with N-methylmaleimide under microwave irradiation, followed by oxidation of the obtained adducts with DDQ, whereas the 1,2,3-triazole ring results from the cycloaddition reaction of the acetylene moiety with sodium azide. The second strategy first involves the cycloaddition reaction with sodium azide to provide the 1,2,3-triazole ring, followed by methylation of the triazole NH group prior to Diels-Alder reaction with N-methylmaleimide. The last step in this synthesis of novel xanthone-1,2,3-triazole dyads entails oxidation of the cycloadducts with DDQ.
- Albuquerque, Hélio M. T.,Santos, Clementina M. M.,Cavaleiro, José A. S.,Silva, Artur M. S.
-
p. 4732 - 4743
(2015/08/03)
-
- 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
-
p. 5910 - 5913
(2014/05/20)
-
- Catalytic Asymmetric Synthesis of Alkynyl Aziridines: Both Enantiomers of cis-Aziridines from One Enantiomer of the Catalyst
-
Alkynyl aziridines can be obtained from the catalytic asymmetric aziridination (AZ reaction) of alkynyl imines with diazo compounds in high yields and high asymmetric inductions mediated by a chiral boroxinate or BOROX catalyst. In contrast to the AZ reaction with aryl- and alkyl-substituted imines, alkynyl imines react to give cis-substituted aziridines with both diazo esters and diazo acetamides. Remarkably, however, the two diazo compounds give different enantiomers of the cis-aziridine from the same enantiomer of the catalyst. Theoretical considerations of the possible transition states for the enantiogenic step reveal that the switch in enantiomers results from a switch from Si-face to Re-face addition to the imine, which in turn is related to a switch from reaction with an E-imine in the former and a Z-isomer of the imine in the latter. The imine did it: The aziridination of alkynyl imines with diazo esters and diazo acetamides gives cis-aziridines with very high enantioselectivities. The absolute configuration of the cis-aziridine is reversed for the two diazo compounds even though the same enantiomer of the catalyst is used. The alkynyl imines can isomerize under the reaction conditions and the enantiomeric switch is proposed to result from the preferential reaction of E-imine with diazo esters and Z-imines with diazo acetamides.
- Guan, Yong,L?pez-Alberca, Maria P.,Lu, Zhenjie,Zhang, Yu,Desai, Aman A.,Patwardhan, Aniruddha P.,Dai, Yijing,Vetticatt, Mathew J.,Wulff, William D.
-
p. 13894 - 13900
(2016/02/18)
-
- Enzyme and Gold Catalysis: A New Enantioselective Entry into Functionalized 4-Hydroxy-2-pyrrolines
-
A new route toward functionalized pyrrolines starting from acetylenic aldehydes was developed. Key steps involved a ?hydroxynitrile lyase catalyzed asymmetric hydrocyanation of acetylenic aldehydes and a gold-catalyzed cyclization of substituted acetylene-containing amino alcohols. Georg Thieme Verlag Stuttgart, New York.
- Ritzen, Bas,Richelle, Gaston J. J.,Brocken, Laurens,Van Delft, Floris L.,Rutjes, Floris P. J. T.
-
p. 270 - 274
(2014/02/14)
-
- Catalytic Enantioselective Quick Route to Aldol-Tethered 1,6- and 1,7-Enynes from ω-Unsaturated Aldehydes
-
An effective asymmetric route to functionalized 1,6- and 1,7-enynes has been developed based on a direct cross-aldol reaction between ω-unsaturated aldehydes and propargylic aldehydes (α,β-ynals) promoted by combined α,α-dialkylprolinol ether/Br?nsted acid catalysis. This synergistic activation strategy is key to accessing the corresponding aldol adducts with high stereoselectivity, both enantio- and diastereoselectivity. The aldol reaction also proceeds well with propargylic ketones (α,β-ynones) thus enabling a stereocontrolled access to the corresponding tertiary alcohols. The utility of these adducts, which are difficult to prepare through standard methodology, is demonstrated by their transformation into trisubstituted bicyclic enones using standard Pauson-Khand conditions.
- García, Jesús M.,Odriozola, José M.,Razkin, Jesús,Lapuerta, Irati,Odriozola, Amaiur,Urruzuno, I?aki,Vera, Silvia,Oiarbide, Mikel,Palomo, Claudio
-
supporting information
p. 15543 - 15554
(2016/02/18)
-
- Efficient one-pot preparation of methylthio arylbutadiynes by double elimination protocol
-
A novel and efficient method for preparation of methylthio arylbutadiynes (Ar-C≡C-C≡C-SCH3) was described, and a series of compounds have been expediently obtained by the one-pot protocol starting from methylthiomethyl phenyl sulfone (MP-S) and arylpropargyl aldehydes. The mechanism was discussed on the basis of trapping and characterization of key intermediates. The results from experiments indicated that the reaction involved the initial nucleophilic addition of MP-S to arylpropargyl aldehydes to produce an intermediate carrying two leaving groups and subsequent double elimination reactions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications to view the free supplemental file.
- Su, Qiong,Yan, Hong,Gao, Shi-Chao,Xie, De-Xun,Cai, Qing-Yun,Shao, Guang,Peng, Zhi-Hong,An, De-Lie
-
p. 2648 - 2655
(2013/07/26)
-
- Bronsted acid catalyzed and NIS-promoted cyclization of diynones: Selective synthesis of 4-pyrone, 4-pyridone, and 3-pyrrolone derivatives
-
Bronsted acid catalyzed tandem cyclization was found to be highly effective for the preparation of a series of polysubstituted 4-pyrones from diynones (yield up to 99%). 4-Pyridone and 3-pyrrolone derivatives were also selectively synthesized by employing NIS and/or Bronsted acid. NIS as an electrophilic reagent could promote these reactions efficiently and rapidly under very mild reaction conditions.
- Qiu, Yi-Feng,Yang, Fang,Qiu, Zi-Hang,Zhong, Mei-Jin,Wang, Li-Jing,Ye, Yu-Ying,Song, Bo,Liang, Yong-Min
-
p. 12018 - 12028
(2014/01/06)
-
- A simple and efficient method for mild and selective oxidation of propargylic alcohols using TEMPO and calcium hypochlorite
-
Oxidation of propargylic alcohols to the corresponding aldehydes and ketones was achieved at room temperature using 2,2,6,6-tetramethylpiperidine-1- oxyl (TEMPO) and calcium hypochlorite (Ca(OCl)2). Propargylic diols yielded corresponding dialdehydes as the product. This system was found to be very efficient for both the electron donating and electron withdrawing groups such as methoxy and nitro substituted alcohols, respectively. This method does not require any additives and demonstrates the controlled, selective oxidation of propargylic alcohols affording up to 97% isolated yield. The Royal Society of Chemistry 2013.
- Reddy, Sabbasani Rajasekhara,Chadha, Anju
-
p. 14929 - 14933
(2013/09/02)
-
- Total synthesis of 7′-desmethylkealiiquinone
-
The total synthesis of an analogue of the marine alkaloid kealiiquinone has been completed through application of an intramolecular Diels-Alder reaction of an imidazole-containing enyne. Oxidative aromatization of the lactone adduct and N-methylation faci
- Lima, Heather M.,Sivappa, Rasapalli,Yousufuddin, Muhammed,Lovely, Carl J.
-
p. 2274 - 2277
(2012/06/30)
-
- Oxidation of α-trifluoromethyl alcohols using a recyclable oxoammonium salt
-
A simple, mild method for the oxidation of α-trifluoromethyl alcohols to trifluoromethyl ketones (TFMKs) using the oxoammonium salt 4-acetylamino-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (1) is described. Under basic conditions, oxidation proceeds rapidly and affords good to excellent yields of TFMKs, without concomitant formation of the hydrate. The byproduct of the oxidation, 4-acetylamino-2,2,6,6-tetramethyl-1- piperidinyloxy (1c), is easily recovered and can be conveniently reoxidized to regenerate the oxoammonium salt.
- Kelly, Christopher B.,Mercadante, Michael A.,Hamlin, Trevor A.,Fletcher, Madison H.,Leadbeater, Nicholas E.
-
p. 8131 - 8141
(2013/01/15)
-
- N-heterocyclic carbene-catalyzed annulation of α-cyano-1,4-diketones with ynals
-
In this paper, the first stereoselective annulation reaction between r-cyano-1,4-diketones and ynals, mediated by catalytic amounts of a triazolium salt precatalyst and cocatalytic amounts of a weak carboxylate base, is disclosed. The title transformation proceeds smoothly under mild reaction conditions and generates three contiguous stereogenic centers, one of which is a quaternary acetal carbon. This reaction tolerates a wide variety of electronically distinct substituents on both reaction partners and affords privileged bicyclic scaffolds in 61-90% isolated yields and with up to 20:1 diastereomeric preference.
- Romanov-Michailidis, Fedor,Besnard, Celine,Alexakis, Alexandre
-
supporting information
p. 4906 - 4909,4
(2012/12/12)
-
- N-heterocyclic carbene-catalyzed annulation of α-cyano-1,4-diketones with ynals
-
In this paper, the first stereoselective annulation reaction between r-cyano-1,4-diketones and ynals, mediated by catalytic amounts of a triazolium salt precatalyst and cocatalytic amounts of a weak carboxylate base, is disclosed. The title transformation proceeds smoothly under mild reaction conditions and generates three contiguous stereogenic centers, one of which is a quaternary acetal carbon. This reaction tolerates a wide variety of electronically distinct substituents on both reaction partners and affords privileged bicyclic scaffolds in 61-90% isolated yields and with up to 20:1 diastereomeric preference.
- Romanov-Michailidis, Fedor,Besnard, Céline,Alexakis, Alexandre
-
supporting information
p. 4906 - 4909
(2013/01/15)
-
- PROCESS FOR PRODUCING ALDEHYDES OR KETONES BY OXIDIZING ALCOHOLS WITH OXYGEN
-
Provided is a process for producing aldehydes or ketones by oxidizing alcohols with oxygen, which comprises oxidizing alcohols to aldehydes or ketones in an organic solvent at room temperature with oxygen or air as an oxidant, wherein ferric nitrate (Fe(NO3)3.9H2O), 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) and an inorganic chloride are used as catalysts, the reaction time is 1-24 hours, and the molar ratio of said alcohols, 2,2,6,6-tetramethylpiperidine N-oxyl and the inorganic chloride is 100:1?10:1?10:1?10. The present process has the advantages of high yield, mild reaction conditions, simple operation, convenient separation and purification, recoverable solvents, substrates used therefor being various and no pollution, and therefore it is adaptable to industrialization.
- -
-
Page/Page column 4
(2012/09/10)
-
- Synthesis of trans-A2B2-porphyrins bearing phenylethynyl substituents
-
Efficient and convenient conditions for the preparation of trans-A 2B2-porphyrins bearing two phenylethynyl moieties directly from phenylpropargyl aldehydes and dipyrromethanes of diversified lipophilicity and reactivity have been de
- Nowak-Krol, Agnieszka,Koszarna, Beata,Yoo, Su Yeon,Chrominski, Jan,Weclawski, Marek K.,Lee, Chang-Hee,Gryko, Daniel T.
-
p. 2627 - 2634
(2011/06/20)
-
- Synthesis of pyrazoles via electrophilic cyclization
-
Electrophilic cyclizations of α,β-alkynic hydrazones by molecular iodine were investigated for the synthesis of 4-iodopyrazoles. α,β-Alkynic hydrazones were readily prepared by the reactions of hydrazines with propargyl aldehydes and ketones. When treated with molecular iodine in the presence of sodium bicarbonate, α,β-alkynic hydrazones underwent electrophilic cyclization to afford 4-iodopyrazoles in good to high yields. Iodocyclization was general for a wide range of α,β-alkynic hydrazones and tolerated the presence of aliphatic, aromatic, heteroaromatic, and ferrocenyl moieties with electron-withdrawing and electron-donating substituents.
- Zora, Metin,Kivrak, Arif,Yazici, Ceyda
-
scheme or table
p. 6726 - 6742
(2011/10/09)
-
- Synthesis of pyrazoles via CuI-mediated electrophilic cyclizations of α,β-alkynic hydrazones
-
Synthesis of pyrazoles via electrophilic cyclization of α,β-alkynic hydrazones by copper(I) iodide is described. When treated with copper(I) iodide in the presence of triethylamine in refluxing acetonitrile, α,β-alkynic hydrazones, prepared readily from hydrazines and propargyl aldehydes and ketones, undergo electrophilic cyclization to afford pyrazole derivatives in good to excellent yields. The reaction appears to be general for a variety of α,β-alkynic hydrazones and tolerates the presence of aliphatic, aromatic, and ferrocenyl moieties with electron-withdrawing and electron-donating substituents.
- Zora, Metin,Kivrak, Arif
-
scheme or table
p. 9379 - 9390
(2012/01/06)
-
- Development of a general and practical iron nitrate/TEMPO-catalyzed aerobic oxidation of alcohols to aldehydes/ketones: Catalysis with table salt
-
Oxidation of alcohols is a fundamental transformation related to our daily life. Traditional approaches with at least one stoichiometric amount of oxidants are expensive and cause serious environmental burdens. There are many reports on the aerobic oxidation of simple alcohols such as alkyl or phenyl carbinols and allylic alcohols, which used oxygen or air as the environmentally benign oxidant forming water as the only by-product. However, no such protocol has been reported for allenols and propargylic alcohols. Thus, it still highly desirable to develop efficient room temperature oxidations of alcohols with a wide scope including allenols and propargylic alcohols. In this paper, an efficient and clean aerobic oxidation of so far the widest spectrum of alcohols using 1 atm of oxygen or air, producing aldehydes/ketones at room temperature in fairly high isolated yields mostly within a couple of hours is described. It is interesting to observe that the reaction has been efficiently expedited by a catalytic amount of sodium chloride in easily recoverable 1,2-dichloroethane. A mechanism involving NO and NO2 has been proposed based on the results of the control experiments and GC-MS studies of the in-situ formed gas phase of the reaction mixture.
- Ma, Shengming,Liu, Jinxian,Li, Suhua,Chen, Bo,Cheng, Jiajia,Kuang, Jinqiang,Liu, Yu,Wan, Baoqiang,Wang, Yuli,Ye, Juntao,Yu, Qiong,Yuan, Weiming,Yu, Shichao
-
experimental part
p. 1005 - 1017
(2011/06/17)
-
- Ligand-promoted, copper nanoparticles catalyzed oxidation of propargylic alcohols with TBHP or Air as Oxidant
-
A highly efficient oxidation of propargylic alcohols to ynones was catalyzed by copper nanoparticles (Cu Nps) with TBHP as an oxidant at room temperature. With bipyridine as the ligand, the reaction was accelerated significantly and led in good to excellent yields to a variety of propargylic alcohols. Furthermore, with Cu Nps as the catalyst, molecular oxygen in air could be utilized as oxidant effectively in the presence of bpy ligand. Georg Thieme Verlag Stuttgart - New York.
- Han, Chengyan,Yu, Min,Sun, Weijiang,Yao, Xiaoquan
-
experimental part
p. 2363 - 2368
(2011/10/30)
-
- Lewis acid-catalyzed [3 + 2]Cyclo-addition of alkynes with N -tosyl-aziridines via carbon-carbon bond cleavage: Synthesis of highly substituted 3-pyrrolines
-
A novel, efficient, and highly regioselective Lewis acid-catalyzed [3 + 2] cycloaddition of alkynes with azomethine ylides, which are easily obtained from N-tosylaziridines via C-C bond heterolysis at room temperature was developed. Moderate enantioselect
- Li, Lei,Zhang, Junliang
-
supporting information; body text
p. 5940 - 5943
(2012/01/02)
-
- An SN2′ displacement approach to allenyl acetates
-
Reaction of cuprates derived from R3MgBr/CuI/LiBr (R3 = n-alkyl) with R1CCCH(O2CR2)2 (R1 = sp2 hybridised substituent, R2 = mainly Me, alkyl, Ph) provides access to allenyl esters R1R 3CCCH(O2CR2) (51-88%). Such species are not accessible via rearrangement of precursor propargylic R1R 3C(O2CR2)CCH.
- Asikainen, Martta,Lewis, William,Blake, Alexander J.,Woodward, Simon
-
supporting information; experimental part
p. 6454 - 6456
(2011/01/03)
-
- Organocatalyzed conjugate addition of carbonyl compounds to nitrodienes/nitroenynes and synthetic applications
-
The purpose of this study is to point out the synthetic utility of a new class of Michael acceptors (nitrodienes and nitroenynes). The highly enantioselective organocatalytic Michael addition of carbonyl compounds to these functionalized nitroolefins has been carried out in the presence of (S)-diphenylprolinol silyl ether to achieve some interesting building blocks in high selectivities. The adducts thus obtained can be easily converted by taking advantage of the corresponding unsaturated carbon-carbon bond. In presence of the double bond, metathesis or electrophilic activation could be carried out whereas in the presence of the triple bond electrophilic acti-vation could be conducted. We thus focused on a gold-catalyzed cyclization of the bis-homopropargylic alcohol to afford the corresponding substituted tetrahydrofuran. Then, we also demonstrated that organic and gold catalysts were compatible in a one-pot process. Indeed, we developed a one-pot enantioselective organocatalytic Michael addition to a nitroenyne followed by a gold-catalyzed acetalization/cyclization to achieve tetrahydrofuranyl ethers in high diastereoand enantioselectivities with excellent yields.
- Belot, Sebastien,Quintard, Adrien,Krause, Norbert,Alexakis, Alexandre
-
supporting information; experimental part
p. 667 - 695
(2010/06/22)
-
- UNSATURATED HETEROCYCLIC INHIBITORS OF NECROPTOSIS
-
The invention features new small molecule inhibitors of necroptosis. The compounds of the invention are described by Formulas (I) and (II). The invention also features pharmaceutical compositions that include compounds of Formula (I) and (II). The compounds and compositions of the invention are also featured in kits and in methods of treatment of conditions that include neurodegenerative diseases, ischemic brain and heart injuries, and head trauma.
- -
-
Page/Page column 46
(2010/07/09)
-
- Enantioselective one-pot organocatalytic michael addition/goldcatalyzed tandem acetalization/cyclization
-
Au-rganocatalytic reaction: A one-pot process consisting of a Michael addition to a nitroenyne and a subsequent acetalization/ cyclization is reported (see scheme; TMS=trimethylsilyl), which results in the formation of nitro-substituted tetrahydrofuranyl ethers with high diastereo- and enantioselectivities. Organocatalysis and gold catalysis are compatible and complementary in a one-pot process
- Belot, Sebastien,Vogt, Kim A.,Besnard, Celine,Krause, Norbert,Alexakis, Alexandre
-
supporting information; experimental part
p. 8923 - 8926
(2010/03/03)
-
- Structure-activity relationship study of a novel necroptosis inhibitor, necrostatin-7
-
Necroptosis is a regulated caspase-independent cell death mechanism characterized by morphological features resembling non-regulated necrosis. Necrotatin-7 (Nec-7), a novel potent small-molecule inhibitor of necroptosis, is structurally distinct from previously described necrostatins (Nec-1, Nec-3, Nec-4 and Nec-5). Here, we describe a series of structural modifications and the structure-activity relationship (SAR) of the Nec-7 series for inhibiting necroptosis.
- Zheng, Weihong,Degterev, Alexei,Hsu, Emily,Yuan, Junying,Yuan, Chengye
-
scheme or table
p. 4932 - 4935
(2009/05/26)
-
- Convenient synthesis of arylpropargyl aldehydes and 4-aryl-3-butyn-2-ones from arylacetylenes and amide acetals
-
The reaction of arylacetylenes 1 and N,N-dimethylformamide dimethylacetal (2a, DMF-DMA) afforded the corresponding arylpropargyl aldehydes 3 in moderate yields. Similarly, the reaction of 1 and N,N-dimethylacetamide dimethylacetal (2b, DMA-DMA) gave 4-aryl-3-butyn-2-ones 4.
- Lee, Ka Young,Lee, Mi Jung,GowriSankar, Saravanan,Kim, Jae Nyoung
-
p. 5043 - 5046
(2007/10/03)
-
- High birefringent bisdiynes and hexatriynes based on double elimination of β-substituted sulfones
-
In order to realize high birefringence, acetylenes with long molecular size such as bis(phenyldiynyl)benzenes 1 and diphenylhexatriynes 4 are synthesized successfully on the basis of double elimination of the β-substituted sulfones which can be prepared e
- Ye, Fangguo,Orita, Akihiro,Yaruva, Jayamma,Hamada, Tatsuya,Otera, Junzo
-
p. 528 - 529
(2007/10/03)
-
- Peralkynylated buta-1,2,3-trienes: Exceptionally low-rotational barriers of camulenic C=C bonds in the range of those of peptide C-N bonds
-
A variety of 1,1,4,4-tetraal kynylbutatrienes and 1,4-dialkynylbutatrienes was synthezized by dimerization of the corresponding gem-dibromoolefins. Both 1H and 13C NMR spectroscopy indicated that the di- and tetraalkynylated butatrie
- Auffrant, Audrey,Jaun, Bernhard,Jarowski, Peter D.,Houk, Kendall N.,Diederich, Francois
-
p. 2906 - 2911
(2007/10/03)
-
- Reaction of arylpropargyl aldehydes with 2,3-bis-hydroxylamino-2,3-dimethylbutane: Synthesis of 2-(1-hydroxy-4,4,5,5-tetramethylimidazolidin-2-ylidene)-1-arylethanones
-
Reaction of arylpropargyl aldehydes with 2,3-dihydroxylamino-2,3-dimethylbutane results in the formation of 2-(1-hydroxy-4,4,5,5-tetramethylimidazolidin-2-ylidene)-1-arylethanones in high yields (70-80%). Allowing availability of propargyl aldehydes, this method gives new possibilities for the preparation of 2-(1-hydroxy-4,4,5,5-tetramethylimidazolidin-2-ylidene)-1-arylethanones. (C) 2000 Elsevier Science Ltd.
- Tretyakov, Eugene V,Tkachev, Alexey V,Rybalova, Tatyana V,Gatilov, Yurii V,Knight, David W,Vasilevsky, Sergey F
-
p. 10075 - 10080
(2007/10/03)
-
- Unexpected Course of the Reaction of 1,3-Bis(dimethylamino)trimethinium Perchlorate with 3-Substituted Prop-2-ynals Leading to 1-Aryl-2,4,6-triformylbenzenes
-
Reaction of 1,3-bis(dimethylamino)trimethinium perchlorate (1) with 3-substituted prop-2-ynals (4) in acetic anhydride at the presence of ZnBr2 gives upon hydrolysis 1-substituted 2,4,6-triformylbenzenes (6) in low to moderate yield. This reaction is restricted to prop-2-ynals bearing electron rich aromatic substituents at the 3-position.
- Suchy, Petr,Dvorak, Dalimil,Havelkova, Martina
-
p. 119 - 129
(2007/10/03)
-
- Preparation of Arylpropiolate Esters from Trichlorocyclopropenium Cation and Elaboration of the Esters to Unsymmetrical 1,4-Pentadiyn-3-ones and Unsymmetrical Tellurapyranones
-
The addition of aromatic compounds including thiophene, naphthalene derivatives, and some benzene derivatives to trichlorocyclopropenium cation gave nearly quantitative yields of 1-aryl-2,3,3-trichlorocyclopropenes.Alcoholysis of the cyclopropene derivatives gave either arylpropiolate esters or arylpropiolate orthoesters (in the presence of added amine base).The arylpropiolates can be converted to unsymmetrical 1,4-pentadiyn-3-ones by two different approaches.The first approach involved reduction of the arylpropiolate esters with diisobutylaluminum hydride to give the corresponding propargyl alcohol.Pyridinium chlorochromate or manganese dioxide oxidation of the alcohol gave the propargyl aldehydes.Addition of a lithium acetylenide gave a 1,4-pentadiyn-3-ol, which could then be oxidized to the 1,4-pentadiyn-3-one with 10percent chromic acid or manganese dioxide.The second pathway used a Lewis acid mediated coupling of a propargylic acid chloride with a (trimethylsilyl)acetylene to give the 1,4-pentadiyn-3-ones directly.The coupling of 2-thiophenepropiolic acid chloride gave the product of HCl addition to the expected 1,4-diynone.The regiochemistry of addition was determined to be chloride addition to the thiophene-bearing triple bond on the basis of 1H NMR studies.The diynones were converted to unsymmetrical 2,6-disubstituted tellura-4H-pyran-4-ones with disodium telluride anion.
- Wadsworth, Donald H.,Geer, Susan M.,Detty, Michael R.
-
p. 3662 - 3668
(2007/10/02)
-