- Rhodium-Catalyzed Intermolecular Cyclopropanation of Benzofurans, Indoles, and Alkenes via Cyclopropene Ring Opening
-
The generation of metal carbenoids via ring opening of cyclopropenes by transition metals offers a simple entry into highly reactive intermediates. Herein, we describe a diastereoselective intermolecular rhodium-catalyzed cyclopropanation of heterocycles and alkenes using cyclopropenes as carbene precursors with a low loading of a commercially available rhodium catalyst. The reported method is scalable and could be performed with catalyst loadings as low as 0.2 mol %, with no impact to the reaction yield or selectivity.
- Jeyaseelan, Rubaishan,Lautens, Mark,Ross, Rachel J.
-
supporting information
(2020/06/29)
-
- Titanium tetrachloride promoted cyclodehydration of aryloxyketones: Facile synthesis of benzofurans and naphthofurans with high regioselectivity
-
An efficient and facile method for the synthesis of a broad series of benzofurans and naphthofurans is described. The direct intramolecular cyclodehydration of aryloxyketones in the presence of titanium tetrachloride affords the corresponding benzofurans and naphthofurans with good regioselectivity and yields.
- Zhang, Qiu,Luo, Juan,Wang, Bingqiao,Xiao, Xiaoqin,Gan, Zongjie,Tang, Qiang
-
supporting information
p. 1337 - 1340
(2019/04/16)
-
- TBAI/TBHP mediated oxidative cross coupling of ketones with phenols and carboxylic acids: Direct access to benzofurans
-
TBAI/TBHP mediated oxidative cross coupling of phenols and carboxylic acids with ketones has been reported under metal-free, base free, solvent free conditions enabling environmentally benign synthesis of aryloxyketones, acyloxy ketones and benzofurans. Phenoxyketones and acyloxylcarbonyl compounds were synthesized in good to high yields, where as benzofurans were synthesized in moderate yields. This method is operationally simple, works under mild conditions, using commercially available as well as inexpensive TBAI and an oxidant TBHP.
- Santhosh Kumar,Ravikumar,Chinna Ashalu,Rajender Reddy
-
supporting information
p. 33 - 37
(2017/12/11)
-
- Preliminary investigation of 6,7-dihydropyrazolo[1,5-a]pyrazin-4-one derivatives as a novel series of mGlu5 receptor positive allosteric modulators with efficacy in preclinical models of schizophrenia
-
As part of our efforts to identify a suitable back-up compound to our recently disclosed mGlu5 positive allosteric modulator (PAM) clinical candidate VU0490551/JNJ-46778212, this letter details the investigation and challenges of a novel series of 6,7-dihydropyrazolo[1,5-a]pyrazin-4-one derivatives. From these efforts, compound 4k emerged as a potent and selective mGlu5 PAM displaying overall attractive in vitro (pharmacological and ADMET) and PK profiles combined with in vivo efficacy in preclinical models of schizophrenia. However, further advancement of the compound was precluded due to severely limiting CNS-related side-effects confirming the previously reported association between excessive mGlu5 activation and target-related toxicities.
- Conde-Ceide, Susana,Alcázar, Jesús,Alonso De Diego, Sergio A.,López, Silvia,Martín-Martín, María Luz,Martínez-Viturro, Carlos M.,Pena, Miguel-Angel,Tong, Han Min,Lavreysen, Hilde,MacKie, Claire,Bridges, Thomas M.,Daniels, J. Scott,Niswender, Colleen M.,Jones, Carrie K.,MacDonald, Gregor J.,Steckler, Thomas,Conn, P. Jeffrey,Stauffer, Shaun R.,Lindsley, Craig W.,Bartolomé-Nebreda, José Manuel
-
supporting information
p. 429 - 434
(2016/01/09)
-
- Conformational restriction of aryl thiosemicarbazones produces potent and selective anti-Trypanosoma cruzi compounds which induce apoptotic parasite death
-
Chagas disease, caused by Trypanosoma cruzi, is a life-threatening infection leading to approximately 12,000 deaths per year. T. cruzi is susceptible to thiosemicarbazones, making this class of compounds appealing for drug development. Previously, the hom
- Magalhaes Moreira, Diogo Rodrigo,De Oliveira, Ana Daura Travassos,Teixeira De Moraes Gomes, Paulo André,De Simone, Carlos Alberto,Villela, Filipe Silva,Ferreira, Rafaela Salgado,Da Silva, Aline Caroline,Dos Santos, Thiago André Ramos,Brelaz De Castro, Maria Carolina Accioly,Pereira, Valéria Rego Alves,Leite, Ana Cristina Lima
-
p. 467 - 478
(2014/03/21)
-
- Enantioselective synthesis of chiral β-aryloxy alcohols by ruthenium-catalyzed ketone hydrogenation via dynamic kinetic resolution (DKR)
-
A highly efficient enantioselective synthesis of chiral β-aryloxy alcohols by the [RuCl2[(S)-SDP][(R, R)-DPEN]} [(Sa,R, R)-1a; SDP = 7, 7′-bis-(diarylphosphino)-1,1′-spirobiindane; DPEN = trans-1,2-diphenylethylenediamine] complex-ca
- Bai, Wen-Ju,Xie, Jian-Hua,Li, Ya-Li,Liu, Sheng,Zhou, Qi-Lin
-
supporting information; experimental part
p. 81 - 84
(2010/06/16)
-
- Direct conversion of N-methoxy-N-methylamides (Weinreb amides) to ketones via a nonclassical Wittig reaction
-
(Chemical Equation Presented) N-Methoxy-N-methylamides (Weinreb amides) are converted efficiently into ketones by reaction with alkylidenetriphenylphosphoranes and in situ hydrolysis of the product.
- Murphy, John A.,Commeureuc, Aurelien G. J.,Snaddon, Thomas N.,McGuire, Thomas M.,Khan, Tanweer A.,Hisler, Kevin,Dewis, Mark L.,Carling, Robert
-
p. 1427 - 1429
(2007/10/03)
-
- Stereochemical analysis of deuterated alkyl chains by MS/MS
-
Vicinally deuterated sec-alkyl phenyl ethers, CH3(CH2)(m)CH(OPh)CHD(CH2)(n)CH3, display significant differences in mass spectra between threo and erythro stereoisomers. MS/MS experiments, in which parent ions of a single mass are selected and their fragmentation patterns subsequently measured, show that alkene expulsion represents virtually the only decomposition pathway. Two types of MS/MS experiment are reported: mass- analyzed ion kinetic energy (MIKE) spectroscopy of metastable ions and collisionally activated decomposition (CAD) of stable ions. The expulsion of a deuterated alkene from a monodeuterated precursor yields ionized phenol, PhOH·+ (m/z 94). The expulsion of an undeuterated alkene yields PhOD·+ (m/z 95). Without exception, the ratios (PhOD·+/PhOH·+) from precursors in the threo series have values greater than their diastereomers in the erythro series. The ratio of ratios, r = PhOD·+/PhOH·+ for the threo divided by PhOD·+/PhOH·+ for the erythro, has a value of 1.2 for the 2- phenoxy-3-deuteriobutanes and larger values for all of the higher homologues up through the monodeuterated phenoxyoctanes (m + n = 4). The highest degree of stereoselectivity, r = 5.8, is measured for 3-phenoxy-4-deuteriohexane. Experiments with multiply deuterated analogues show that alkene elimination is highly regioselective, unlike the corresponding decompositions of ionized sec-alcohols or their acetates. The fact that a large fraction of ionized sec-alkyl phenyl ethers undergo stereospecific syn-elimination means that mass spectrometry has a useful capacity to distinguish one isotopically labeled diastereomer from another.
- Morizur,Taphanel,Mayer, Philip S.,Morton, Thomas Hellman
-
p. 381 - 387
(2007/10/03)
-
- Serotonin antagonists
-
A compound of the formula EQU1 or an acid addition salt thereof wherein R1 and R2 are the same or different and each is a phenyl or thien-2-yl group optionally substituted in one or more positions by a substituent selected from the class consisting of halogen, lower alkyl, lower alkoxy, hydroxy, lower alkylthio, phenyl, phenoxy, phenyl-(lower-alkyl) and phenyl-(lower-alkoxy), each of the said phenyl, phenoxy, phenyl-(lower-alkyl) and phenyl-(lower-alkoxy) substituent groups being optionally substituted in one or more positions by a member selected from the class consisting of halogen, lower alkyl, lower alkoxy, hydroxy, and lower alkylthio; A1 is a divalent straight or branched alkylene group containing from two to six carbon atoms and one or two divalent atoms which are each an oxygen or sulphur atom, provided that there are at least two carbon atoms between the divalent atom and the --NH-- group and between the two divalent atoms; and A2 is the methylene group --CH2 --.
- -
-
-