604-61-5Relevant articles and documents
Divergent Synthesis of Highly Substituted Pyridines and Benzenes from Dienals, Alkynes, and Sulfonyl Azides
Luo, Han,Li, You,Du, Luan,Xin, Xiaolan,Wang, Tao,Han, Jingpeng,Tian, Yi,Li, Baosheng
supporting information, p. 7883 - 7887 (2021/10/20)
Divergent synthesis is extremely important for the highly efficient preparation of structurally diverse target molecules. Herein, we describe a multicomponent cascade reaction, which allows access to highly substituted pyridines and benzenes by combining four individual steps in a one-pot manner from the same set of readily available starting materials. The azepine intermediates were first used as the precursors for 6π-electrocyclization to construct highly substituted pyridines and benzenes in a tunable manner.
Palladium-Catalyzed Direct Oxidative Coupling of Iodoarenes with Primary Alcohols Leading to Ketones: Application to the Synthesis of Benzofuranones and Indenones
Suchand, Basuli,Sreenivasulu, Chinnabattigalla,Satyanarayana, Gedu
, p. 4832 - 4843 (2019/07/31)
In the present study, a palladium-catalyzed direct oxidative acylation through cross-dehydrogenative coupling has been investigated, utilizing readily available primary alcohols as acylating sources. Overall, this oxidative coupling proceeds via three distinct transformations such as oxidation, radical formation, and cross-coupling in one catalytic process. This protocol does not involve the assistance of a directing group or activation of the carbonyl group by any other means. Furthermore, this reaction made use of no toxic CO gas as carbonylating agent; instead, feedstock primary alcohols have been utilized as acylation source. Notably, the synthesis of benzofuranones and indenones is enabled. This strategy was also applied to the synthesis of n-butylphthalide, fenofibrate, pitofenone, and neo-lignan.
Palladium-Catalyzed Environmentally Benign Acylation
Suchand, Basuli,Satyanarayana, Gedu
, p. 6409 - 6423 (2016/08/16)
Recent trends in research have gained an orientation toward developing efficient strategies using innocuous reagents. The earlier reported transition-metal-catalyzed carbonylations involved either toxic carbon monoxide (CO) gas as carbonylating agent or functional-group-assisted ortho sp2 C-H activation (i.e., ortho acylation) or carbonylation by activation of the carbonyl group (i.e., via the formation of enamines). Contradicting these methods, here we describe an environmentally benign process, [Pd]-catalyzed direct carbonylation starting from simple and commercially available iodo arenes and aldehydes, for the synthesis of a wide variety of ketones. Moreover, this method comprises direct coupling of iodoarenes with aldehydes without activation of the carbonyl and also without directing group assistance. Significantly, the strategy was successfully applied to the synthesis n-butylphthalide and pitofenone.
Insertion of N-Tosylacetimidates/Acetimidamides onto Arynes via [2 + 2] Cycloaddition
Kranthikumar, Ramagonolla,Chegondi, Rambabu,Chandrasekhar, Srivari
, p. 2451 - 2459 (2016/04/01)
A novel insertion reaction of N-tosylacetimidates and N-tosylacetimidamides onto arynes via a benzocyclobutene intermediate followed by ring cleavage is developed to afford o-benzylbenzoic acid derivatives in good yields. Interestingly, the use of cyclic
Design, characterization, computational studies, and pharmacological evaluation of substituted-N′-[(1E) substituted-phenylmethylidene] benzohydrazide analogs
Bala, Suman,Uppal, Goldie,Kamboj, Sunil,Saini, Vipin,Prasad
, p. 2755 - 2767 (2013/07/26)
A series of substituted-N′-[(1E)-substituted-phenylmethylidene] benzohydrazide analogs were synthesized and authenticated by TLC, UV-Visible, FTIR, and NMR spectroscopic techniques. The physicochemical similarity of the new analogs with standard drugs was assessed by calculating from a set of ten physicochemical properties using software programs. The information so obtained can be related to prediction of biological activity for important targets. All the target compounds 4a-n were evaluated for their antioxidant, anti-inflammatory, and antimicrobial activity using different in vitro models. The test compounds demonstrated good similarity values with respect to the standard drugs. The compounds 4c, 4d, and 4e have emerged as important lead compounds showing potential anti-inflammatory; and 4b, 4f, and 4c having antioxidant profile. While studying MIC against bacterial strains 4c, 4f, 4i, 4k, and 4m were most active among all the target compounds. All compounds were found to have very good antifungal activity. The compounds having nitro substitution at the arylidene moiety i.e., 4c and 4f showed the most potent antifungal as well as antibacterial activities. While studying total antioxidant activity, all target compounds were found to have good antioxidant activity.
Preparation of aryl ketones via Ni-catalyzed Negishi-coupling reactions with acid chlorides
Kim, Seung-Hoi,Rieke, Reuben D.
experimental part, p. 1523 - 1526 (2011/05/16)
A Ni-catalyst-catalyzed cross-coupling reaction of organozinc reagents with acid chlorides has been successfully developed. Mild reaction conditions were required to complete the coupling reactions affording the corresponding aryl ketones in good to excellent yields.
Synthesis of chiral 5-aryltetrahydrofuran-2-ones via yeast bioreduction of γ-keto acids and their esters
Mahmoodi,Yousefi-Malekroudi
, p. 365 - 368 (2007/10/03)
Enantioselective reduction of γ-keto acids and related γ-keto esters with Saccharomyces cerevisiae (baker's yeast) leads to the formation of the corresponding chiral 5-aryltetrahydrofuran-2-ones in satisfactory chemical and optical yields. Pleiades Publishing, Inc., 2006.
A Surprising Solid-Phase Effect: Development of a Recyclable "Traceless" Linker System for Reactions on Solid Support
Braese, Stefan,Enders, Dieter,Koebberling, JOhannes,Avamaria, Frank
, p. 3413 - 3415 (2007/10/03)
Keywords: arenes; asymmetric synthesis; C-C coupling; solid-phase synthesis; triazenes
An improved method for preparation of carboxylic esters using CsF- celite/alkyl halide/CH3CN combination
Lee, Jong Chan,Choi, Youngsup
, p. 2021 - 2026 (2007/10/03)
A new method for efficient and chemoselective esterification of carboxylic acids in CsF-Celite/alkyl halide/CH3CN reaction system is described.
Preparation and Chemistry of the Active Copper Species Derived from CuI*PBu3, CuI*PPh3, and CuCN*nLiX Complexes
Rieke, Reuben D.,Stack, Douglas E.,Dawson, Bryan T.,Wu, Tse-Chong
, p. 2483 - 2491 (2007/10/02)
The preparation of highly reactive copper by the reduction of CuI*PBu3, CuI*PPh3, and CuCN*nLiX copper(I) complexes with the preformed lithium naphthalenide is described.It was found, for all three Cu(I) complexes, that the reduction temperature proved crucial to reactivity of the zerovalent copper species as measured by the ability of the active copper to undergo oxidative addition to carbon-halogen bonds.The lower the reduction temperature the more reactive the zerovalent copper species becomes.The low-temperature reduction allows for the formation of highly reactive copper from CuCN*nLiX complexes.This active copper species undergoes oxidative addition to alkyl and aryl bromides in high yield to form the corresponding organocopper reagent directly without the need for other organometallic precursors.Moreover, the alkyl and aryl bromides can obtain a wide range of functional groups as they are not affected in the oxidative addition step.The functionalized organocopper reagents derived from CuCN*nLiX based active copper are the reagent of choice in the cross-coupling of acid chlorides to produce ketones as well as the 1,4-addition reaction with enones.The lack of phosphines associated with organocopper reagents stemming from CuCN-based active copper makes product isolation more facile.While the functionalized organocopper reagents derived from CuCN*nLiX complexes provide higher isolated yields in the formentioned reactions, they are not nucleophilic enough to undergo inter- or intramolecular epoxide openings.The use of both CuI*PBu3 and CuI*PPh3 Cu(I) complexes in the intramolecular epoxide openings of aryl bromoepoxides is presented.The regiochemistry, endo vs. exo, was shown to be affected by the Cu(I) complex used to generate the active copper species, the solvent, and the pattern of substitution around the epoxide moiety.The active copper species as well as the resulting organocopper reagents derived from both CuI*PBu3 and CuCN*nLiX were investigated using both 31P and 13C NMR.The data from 31P NMR investigation held some evidence for a highly reduced copper(0)-phosphine complex while the 13C studies of the CuCN*nLiX complexes indicated that these species have limited solubility in THF.
