764-38-5Relevant academic research and scientific papers
An enantiocontrolled entry to the tricyclic polar segment of (+)-fusarisetin A
Kohyama, Aki,Kanoh, Naoki,Kwon, Eunsang,Iwabuchi, Yoshiharu
, p. 517 - 519 (2016)
The tricyclic polar segment of fusarisetin A, designed for preparing analogues for structure-activity relationship studies of the aliphatic segment thereof, has been constructed in an enantiocontrolled manner, featuring the Yamamoto asymmetric epoxidation of a homoallylic alcohol, C3-selective ring-opening of a 3,4-epoxy alcohol, stereocontrolled merger of a γ-lactone with Garner's counterpart, and ruthenium-catalyzed ring-closing metathesis.
Enantioselective Alkylamination of Unactivated Alkenes under Copper Catalysis
Bai, Zibo,Zhang, Heng,Wang, Hao,Yu, Hanrui,Chen, Gong,He, Gang
supporting information, p. 1195 - 1202 (2021/02/05)
An enantioselective addition reaction of various alkyl groups to unactivated internal alkenes under Cu catalysis has been developed. The reaction uses amide-linked aminoquinoline as the directing group, 4-alkyl Hantzsch esters as the donor of alkyl radicals, and rarely used biaryl diphosphine oxide as a chiral ligand. β-lactams featuring two contiguous stereocenters at Cβ and the β substituent can be obtained in good yield with excellent enantioselectivity. Mechanistic studies indicate that a nucleophilic addition of the alkyl radical to CuII-coordinated alkene is the enantio-determining step.
A Supramolecular Strategy for Selective Catalytic Hydrogenation Independent of Remote Chain Length
Bender, Trandon A.,Bergman, Robert G.,Raymond, Kenneth N.,Toste, F. Dean
supporting information, p. 11806 - 11810 (2019/08/22)
Performing selective transformations on complex substrates remains a challenge in synthetic chemistry. These difficulties often arise due to cross-reactivity, particularly in the presence of similar functional groups at multiple sites. Therefore, there is a premium on the ability to perform selective activation of these functional groups. We report here a supramolecular strategy where encapsulation of a hydrogenation catalyst enables selective olefin hydrogenation, even in the presence of multiple sites of unsaturation. While the reaction requires at least one sterically nondemanding alkene substituent, the rate of hydrogenation is not sensitive to the distance between the alkene and the functional group, including a carboxylate, on the other substituent. This observation indicates that only the double bond has to be encapsulated to effect hydrogenation. Going further, we demonstrate that this supramolecular strategy can overcome the inherent allylic alcohol selectivity of the free catalyst, achieving supramolecular catalyst-directed regioselectivity as opposed to directing-group selectivity.
Copper-Catalyzed Oxy-Alkenylation of Homoallylic Alcohols to Generate Functional syn-1,3-Diol Derivatives
Holt, Dean,Gaunt, Matthew J.
supporting information, p. 7857 - 7861 (2015/06/30)
A novel method for the synthesis of a wide range of functionalized 1,3-diol derivatives is reported. Employing a copper-catalyzed oxy-alkenylation strategy, a range of readily available, substituted homoallylic alcohol derivatives and alkenyl(aryl) iodonium salts combine to form syn-1,3-carbonates in excellent yield and with high selectivity. Furthermore, the products formed are amenable to an iterative reaction sequence, thus affording highly complex polyketide-like fragments. Polyols: The reported copper-catalyzed oxy-alkenylation strategy works well for a range of readily available, substituted homoallylic alcohol derivatives and alkenyl(aryl) iodonium salts to form syn-1,3-carbonates in excellent yield and high selectivity. Furthermore, the products formed are amenable to an iterative reaction sequence, thus affording highly complex polyketide-like fragments.
Isothiourea-mediated asymmetric functionalization of 3-alkenoic acids
Morrill, Louis C.,Smith, Samuel M.,Slawin, Alexandra M. Z.,Smith, Andrew D.
, p. 1640 - 1655 (2014/03/21)
Isothiourea HBTM-2.1 promotes the catalytic asymmetric α- functionalization of 3-alkenoic acids through formal [2 + 2] cycloadditions with N-tosyl aldimines and formal [4 + 2] cycloadditions with either 4-aryltrifluoromethyl enones or N-aryl-N-aroyl diazenes, providing useful synthetic building blocks in good yield and with excellent enantiocontrol (up to >99% ee). Stereodefined products are amenable to further synthetic elaboration through manipulation of the olefinic functionality.
Influence of the chemical structure on odor qualities and odor thresholds in homologous series of alka-1,5-dien-3-ones, alk-1-en-3-ones, alka-1,5-dien-3-ols, and alk-1-en-3-ols
Lorber, Katja,Schieberle, Peter,Buettner, Andrea
, p. 1025 - 1031 (2014/03/21)
Odor qualities and odor thresholds in air in homologous series of synthesized alk-1-en-3-ols and alka-1,5-dien-3-ols and their corresponding ketones were evaluated by gas chromatography-olfactometry. In the series of the alk-1-en-3-ols and alk-1-en-3-ones the odor quality changed successively from pungent for the compounds with five carbon atoms via metallic, vegetable-like for the six- and seven-carbon odorants to mushroom-like for the compounds with eight and nine carbon atoms. With further increase in chain length the mushroom-like impression decreased and changed to citrus-like, soapy, or herb-like. In both series, two odor threshold minima were found for the six-carbon and also for the eight- and nine-carbon odorants, respectively. In contrast to this, the odor qualities in the series of the (Z)- and (E)-alka-1,5-dien-3-ols and their corresponding ketones did not change significantly with geranium-like, metallic odors and an increasing mushroom-like odor note with increasing chain length. The lowest thresholds were found for the eight- and nine-carbon (Z)-compounds, respectively.
Influence of the chemical structure on odor qualities and odor thresholds in homologous series of alka-1,5-dien-3-ones, alk-1-en-3-ones, alka-1,5-dien-3-ols, and alk-1-en-3-ols
Lorber, Katja,Schieberle, Peter,Buettner, Andrea
, p. 1025 - 1031 (2015/04/22)
Odor qualities and odor thresholds in air in homologous series of synthesized alk-1-en-3-ols and alka-1,5-dien-3-ols and their corresponding ketones were evaluated by gas chromatography-olfactometry. In the series of the alk-1-en-3-ols and alk-1-en-3-ones the odor quality changed successively from pungent for the compounds with five carbon atoms via metallic, vegetable-like for the six- and seven-carbon odorants to mushroom-like for the compounds with eight and nine carbon atoms. With further increase in chain length the mushroom-like impression decreased and changed to citrus-like, soapy, or herb-like. In both series, two odor threshold minima were found for the six-carbon and also for the eight- and nine-carbon odorants, respectively. In contrast to this, the odor qualities in the series of the (Z)- and (E)-alka-1,5-dien-3-ols and their corresponding ketones did not change significantly with geranium-like, metallic odors and an increasing mushroom-like odor note with increasing chain length. The lowest thresholds were found for the eight- and nine-carbon (Z)-compounds, respectively.
Enantiodivergent and γ-selective asymmetric allylic amination
Wang, Jianmin,Chen, Jie,Kee, Choon Wee,Tan, Choon-Hong
supporting information; experimental part, p. 2382 - 2386 (2012/05/19)
Double agent: The title reaction using the guanidine catalyst 1 can deliver both enantiomers of the product with excellent enantioselectivity by judicious choice of the double bond geometry of the the β,γ-unsaturated carbonyl compound. Computational studies reveal the possible origin of the inversed enantioselectivity, and the potential for enantiodivergent synthesis chiral amine-containing substrates is attractive. Copyright
METHOD FOR HYDROFORMYLATION
-
Page/Page column 8-9, (2010/10/03)
The present invention relates to a process for the hydroformylation of compounds of the formula (I), where X is C, P(Rx), P(O—Rx) S or S(═O), where Rx is H, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl; A is a divalent bridging group having from 1 to 4 bridging atoms; and R1 is H, alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl; or salts thereof; in which the compound of the formula (I) is reacted with carbon monoxide and hydrogen in the presence of a catalyst comprising a complex of a metal of transition group VIII with a compound of the formula (II), where Pn is a pnicogen atom; W is a divalent bridging group having from 1 to 8 bridging atoms; R2 is a functional group capable of forming an intermolecular, noncovalent bond with the group —X(═O)OH; R3, R4 are each alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl; a, b, c are each 0 or 1; and Y1, Y2 and Y3 are each O, S, NRa or SiRbRc; and also compounds of the formula (II.a), where W′ is a divalent bridging group having from 1 to 5 bridging atoms between the flanking bonds, Z is O, S, S(═O), S(═O)2, N(RIX) or C(RIX)(RX); and RI to RX are each, independently of one another, H, halogen, nitro, cyano, amino, alkyl, etc.; or two radicals RI, RII, RIV, RVI, RVIII and RIX together represent the second part of a double bond.
A detailed investigation of the aza-prins reaction
Dobbs, Adrian P.,Guesne, Sebastien J. J.,Parker, Robert J.,Skidmore, John,Stephenson, Richard A.,Hursthouse, Mike B.
supporting information; experimental part, p. 1064 - 1080 (2010/06/13)
The development of a Lewis acid-promoted aza-Prins reaction to form piperidines and pyrrolidines is described. Indium trichloride has been found to be a highly successful and mild Lewis acid for promoting this reaction. A thorough mechanistic investigation is described, including the factors that influence the formation of the 5- or 6-membered ring product(s). The Royal Society of Chemistry.
