127404-73-3Relevant academic research and scientific papers
Palladium-Catalyzed Direct C-H Arylation of 3-Butenoic Acid Derivatives
Yang, Shan,Liu, Lingling,Zhou, Zheng,Huang, Zhibin,Zhao, Yingsheng
, p. 296 - 299 (2021/01/13)
We report herein a direct method to synthesize 4-aryl-3-butenoic acid through a carboxylic-acid-directed oxidative Heck reaction. The various 4-aryl-3-butenoic acids are easily prepared in moderate to good yields. In view of the promising bioactivity of 4-phenyl-3-butenoic acid previously reported, its derivatives reported here may be bioactive.
Enantioselective Synthesis of γ-Lactams by Lewis Base Catalyzed Sulfenoamidation of Alkenes
Panger, Jesse L.,Denmark, Scott E.
supporting information, p. 2501 - 2505 (2020/01/03)
A method for the catalytic, enantioselective, intramolecular 1,2-sulfenoamidation of alkenes is described. Lewis base activation of a suitable sulfur electrophile generates an enantioenriched, thiiranium ion intermediate from a β,γ-unsaturated sulfonyl ca
Intramolecular Cyclization of Vinyldiazoacetates as a Versatile Route to Substituted Pyrazoles
Drikermann, Denis,G?rls, Helmar,Kerndl, Valerie,Vilotijevic, Ivan
supporting information, p. 1158 - 1162 (2020/07/20)
Vinyldiazo compounds undergo a thermal electrocyclization to form pyrazoles in yields of up to 95percent. The reactions are operationally simple, use readily available starting materials, require no intervention of a catalyst, and enable the synthesis of mono-, di- A nd tri-substituted pyrazoles. With the ability to produce highly substituted pyrazoles and the flexibility in installing various types of substituents, this method constitutes a new entry to this valuable heterocyclic scaffold and may be of interest to all branches of the chemical industry.
Synthesis of [18 F]-γ-Fluoro-α,β-unsaturated Esters and Ketones via Vinylogous 18 F-Fluorination of α-Diazoacetates with [18 F]AgF
Brooks, Allen F.,Ichiishi, Naoko,Jackson, Isaac M.,Lee, So Jeong,Sanford, Melanie S.,Scott, Peter J. H.,Thompson, Stephen
supporting information, p. 4401 - 4407 (2019/11/21)
This communication reports a method for the vinylogous radiofluorination of α-diazoacetates to generate [18 F]-γ-fluoro-α,β-unsaturated esters and ketones in moderate to good radiochemical yields. The method uses no-carrier-added [18 F]AgF and is compatible with aromatic and non-aromatic substrates and a number of different functional groups. The labeling method is showcased in the synthesis of a fluorinated cholest-5-en-3-one derivative as well as a difluorinated product pertinent to drug discovery.
HFIP Solvent Enables Alcohols to Act as Alkylating Agents in Stereoselective Heterocyclization
Zhu, Yuxiang,Colomer, Ignacio,Thompson, Amber L.,Donohoe, Timothy J.
supporting information, p. 6489 - 6493 (2019/05/06)
A new method for the stereoselective synthesis of highly functionalized oxygen heterocycles using allyl or benzyl alcohols as alkylating agents is presented. The process is efficient and atom economic, generating water as the only stoichiometric byproduct. Substoichiometric amounts of Ti(OiPr)4 in HFIP solvent are key to this reactivity, and the method tolerates a broad substitution pattern on both the alcohol initiator and homoallylic alcohol substrate. Preliminary mechanistic studies reveal in situ formation of a titanium complex with HFIP which may initiate the cyclization reaction. Further stereoselective functionalization of the products allows access to a diverse range of interesting heterocyclic structures.
Stereoselective Ring-Opening of gem-Difluorocyclopropanes: An Entry to Stereo-defined (E,E)- and (E,Z)-Conjugated Fluorodienes
Specklin, Simon,Fenneteau, Johan,Subramanian, Parthasarathi,Cossy, Janine
supporting information, p. 332 - 336 (2018/01/17)
The ring-opening of gem-difluorocyclopropyl acetaldehydes producing selectively (E,E)- and (E,Z)-conjugated fluorodienals is described. Two stereo-divergent methods are presented to access both stereoisomers from a common precursor, in high yield and selectivity. The mechanistic aspect of these transformations is discussed.
Direct palladium-catalyzed carbonylative transformation of allylic alcohols and related derivatives
Wu, Fu-Peng,Peng, Jin-Bao,Fu, Lu-Yang,Qi, Xinxin,Wu, Xiao-Feng
supporting information, p. 5474 - 5477 (2017/11/06)
A direct, palladium-catalyzed, carbonylative transformation of allylic alcohols for the synthesis of β,γ-unsaturated carboxylic acids has been developed. With formic acid as the CO source, various allylic alcohols were conveniently transformed into the corresponding β,γ-unsaturated carboxylic acids with excellent linear and (E)-selectivity. The reaction was performed under mild conditions; toxic CO gas manipulation and high-pressure equipment were avoided in this procedure.
Efficient Pd-Catalyzed Regio- and Stereoselective Carboxylation of Allylic Alcohols with Formic Acid
Fu, Ming-Chen,Shang, Rui,Cheng, Wan-Min,Fu, Yao
supporting information, p. 8818 - 8822 (2017/07/11)
Formic acid is efficiently used as a C1 source to directly carboxylate allylic alcohols in the presence of a low loading of palladium catalyst and acetic anhydride as additive to afford β,γ-unsaturated carboxylic acids with excellent chemo-, regio-, and stereoselectivity. The reaction proceeds through a carbonylation process with in situ-generated carbon monoxide under mild conditions, avoiding the use of high-pressure gaseous CO. A bisphosphine ligand with a large bite angle (4,5-bis{diphenylphosphino}-9,9-dimethylxanthene, Xantphos) was found to be uniquely effective for this transformation. The regio- and stereoconvergence of this reaction is ascribed to the thermodynamically favored isomerization of the allylic electrophile in the presence of the palladium catalyst.
Method for preparing beta, gama-unsaturated carboxylic acid compound
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Paragraph 0041; 0042; 0043; 0044; 0045; 0046; 0047-0054, (2017/12/04)
The invention provides a method for preparing a beta, gamma-unsaturated carboxylic acid compound. The method comprises the steps of making an allylic alcohol compound of a formula 1 or a formula 2 react with formic acid in the presence of a palladium catalyst, a phosphorous ligand, acid anhydride and an organic solvent to obtain the beta, gamma-unsaturated carboxylic acid compound of a formula 3 or formula 4, wherein R1, R2 and R3 are defined in the description. Formic acid is utilized as a carboxylation reagent, and the beta, gamma-unsaturated carboxylic acid compound is low in price, safe, stable and low in toxicity; the yield is high, the operation is simple, and the economy is high; compared with an existing compounding method, the use of toxic gas carbon monoxide and/or an equivalent quantity of reactive metal reagents is avoided, and the method meets requirements for environment-friendly chemistry; in addition, the dose of catalysts is small, the reaction condition is mild, the reactant is high in conversion rate and product yield, and the method has a very good industrial prospect.
A Chiral Electrophilic Selenium Catalyst for Highly Enantioselective Oxidative Cyclization
Kawamata, Yu,Hashimoto, Takuya,Maruoka, Keiji
supporting information, p. 5206 - 5209 (2016/05/19)
Chiral electrophilic selenium catalysts have been applied to catalytic asymmetric transformations of alkenes over the past two decades. However, highly enantioselective reactions with a broad substrate scope have not yet been developed. We report the first successful example of this reaction employing a catalyst based on a rigid indanol scaffold, which can be easily synthesized from a commercially available indanone. The reaction efficiently converts β,γ-unsaturated carboxylic acids into various enantioenriched γ-butenolides under mild conditions.
