38177-56-9Relevant academic research and scientific papers
Zur Umsetzung von Bis(alkinyl)-Titanocenen mit übergangsmetall-Verbindungen von Cu(II), Pd(II), Pt(II), Fe(III) und Au(III)
Frosch,Back,K?hler,Lang
, p. 226 - 232 (2000)
The reaction behaviour of the bis(alkynyl) titanocenes [Ti](CCR1)(CCR2) {[Ti]=(η5-C5H4SiMe3) 2Ti; 1: R1=R2=Fc, Fc=(η5-C5H4)Fe(η5-C 5H5); 5a: R1=R2=SiMe3; 5b: R1=R2=C6H5; 5c: R1=SiMe3, R2=C6H5} towards MX2 (M=Pd, Pt; X=Cl; M=Cu; X=Cl, Br, OAc, acac) and MCl3 (M=Fe, Au) is described. All reactions are dominated by redox processes. Generally, the reaction of 1 or 5a-5c with AuCl3 or MCl2 (M=Cu, Pd, Pt) produces the titanocene dichloride [Ti]Cl2 (3a) along with the corresponding butadiynes R1CC-CCR2 (4: R1=R2=Fc; 7a: R1=R2=SiMe3; 7b: R1=R2=C6H5; 7c: R1=SiMe3, R2=C6H5) and M(0) (M=Cu, Au, Pd, Pt). As key intermediates the heterobimetallic tweezer complexes {[Ti](CCR1)(CCR2)}MCl2 (M=Cu, Pd, Pt) are formed. These reactions are strongly solvent dependent. While {[Ti](CCFc)2}CuCl2 (2) is readily formed as the main product when 1 is reacted with CuCl2 in diethyl ether, it is found that 2 affords 3a, 4 and Cu(0) on prolonged stirring in tetrahydrofuran. In contrast, complexes 5a-5c produce with equimolar amounts of CuX2 (X=Cl, Br) the compounds [Ti]X2 (3a: X=Cl, 3b: X=Br), R1CC-CCR2 (7a: R1=R2=SiMe3; 7b: R1=R2=C6H5; 7c: R1=SiMe3, R2=C6H5), {[Ti](CCR1)(CCR2)}CuX (6a: R1=R2=SiMe3, X=Cl; 6b: R1=R2=SiMe3, X=Br; 6c: R1=R2=C6H5, X=Cl; 6d: R1=SiMe3; R2=C6H5, X=Cl) as well as 1/n[CuX]n (X=Cl, Br). However, when 5a is treated with Cu(OAc)2 or Cu(acac)2 in a 1:1 ratio, heterobimetallic {[Ti](CCSiMe3)2}CuX (6e: X=OAc, 6f: X=acac) is the only isolated species. Possible mechanisms for the reactions presented are described.
Genome-Based Identification of a Plant-Associated Marine Bacterium as a Rich Natural Product Source
Ueoka, Reiko,Bhushan, Agneya,Probst, Silke I.,Bray, Walter M.,Lokey, R. Scott,Linington, Roger G.,Piel, J?rn
, p. 14519 - 14523 (2018)
The large number of sequenced bacterial genomes provides the opportunity to bioinformatically identify rich natural product sources among previously neglected microbial groups. Testing this discovery strategy, unusually high biosynthetic potential was suggested for the Oceanospirillales member Gynuella sunshinyii, a Gram-negative marine bacterium from the rhizosphere of the halophilic plant Carex scabrifolia. Its genome contains numerous unusual biosynthetic gene clusters for diverse types of metabolites. Genome-guided isolation yielded representatives of four different natural product classes, of which only alteramide A was known. Cytotoxic lacunalides were identified as products of a giant trans-acyltransferase polyketide synthase gene cluster, one of six present in this strain. Cytological profiling against HeLa cells suggested that lacunalide A disrupts CDK signaling in the cell cycle. In addition, chemical studies on model compounds were conducted, suggesting the structurally unusual ergoynes as products of a conjugated diyne–thiourea cyclization reaction.
Total Synthesis of (S)-(-)-(E)-15,16-Dihydrominquartynoic Acid: A Highly Potent Anticancer Agent
Gung, Benjamin W.,Kumi, Godwin
, p. 3488 - 3492 (2004)
The conjugated entriyne natural product, (S)-(E)-15, 16-dihydrominquartynoic acid (1), is synthesized in five linear steps and 30% overall yield from the known aldehyde 11. The key step is a one-pot in situ desilylation/Cadiot-Chodkiewicz coupling reaction affording the entriyne unit. The bromoalkyne 6 with ω-carboxylic acid group was found to undergo a copper-catalyzed cross-coupling reaction producing the desired diyne intermediate 10, while the corresponding ω-ester bromoalkyne 14 failed to couple with triethylsilylacetylene under a variety of conditions.
Ligand-Controlled Regiodivergent Nickel-Catalyzed Hydrocyanation of Silyl-Substituted 1,3-Diynes
Sun, Feilong,Yang, Chengxi,Ni, Jie,Cheng, Gui-Juan,Fang, Xianjie
supporting information, p. 4045 - 4050 (2021/05/26)
A regiodivergent nickel-catalyzed hydrocyanation of 1-aryl-4-silyl-1,3-diynes is reported. When appropriate bisphosphine and phosphine-phosphite ligands are applied, the same starting materials can be converted into two different enynyl nitriles with good
In the optically-multiplexed-
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, (2020/12/30)
A method for optical super-multiplexing using polyynes to provide enhanced images from stimulated Raman microscopy is disclosed. In some exemplary embodiments, the polyynes are organelle-targeted or spectral barcoded. Imaging can be enhanced by using the polyynes to image whole live cells or specific organelles within live cells. The polyynes can also be used in optical data storage (i.e., encoding) and identification (i.e., decoding) applications.
Rh(III)-Catalyzed [3 + 2] Spirocyclization of 2 H-Imidazoles with 1,3-Diynes for the Synthesis of Spiro-[imidazole-indene] Derivatives
Luo, Yi,Liu, Hao,Zhang, Jing,Liu, Man,Dong, Lin
supporting information, p. 7604 - 7608 (2020/10/09)
An effective strategy to synthesize spirocyclic compounds, [imidazole-4,1′-indene], has been efficaciously developed relied on Rh(III)-catalyzed [3 + 2] spirocyclization of 2H-imidazoles and 1,3-diynes with excellent chemselectivity and regioselectivity.
Iron(II)-Based Metalloradical Activation: Switch from Traditional Click Chemistry to Denitrogenative Annulation
Roy, Satyajit,Khatua, Hillol,Das, Sandip Kumar,Chattopadhyay, Buddhadeb
supporting information, p. 11439 - 11443 (2019/07/17)
A unique concept for the intermolecular denitrogenative annulation of 1,2,3,4-tetrazoles and alkynes was discovered by using a catalytic amount of Fe(TPP)Cl and Zn dust. The reaction precludes the traditional, more favored click reaction between an organic azide and alkynes, and instead proceeds by an unprecedented metalloradical activation. The method is anticipated to advance access to the construction of important basic nitrogen heterocycles, which will in turn enable discoveries of new drug candidates.
Unraveling the Mechanism of 1,3-Diyne Cross-Metathesis Catalyzed by Silanolate-Supported Tungsten Alkylidyne Complexes
Schnabel, Tobias M.,Melcher, Daniel,Brandhorst, Kai,Bockfeld, Dirk,Tamm, Matthias
supporting information, p. 9022 - 9032 (2018/06/29)
The benzylidyne complex [PhC≡W{OSi(OtBu)3}3] (1) catalyzed the cross-metathesis between 1,4-bis(trimethylsilyl)-1,3-butadiyne (2) and symmetrical 1,3-diynes (3) efficiently, which gave access to TMS-capped 1,3-diynes RC≡C?C≡CSiMesub
Copper(II)/Palladium(II) catalysed highly selective cross-coupling of terminal alkynes in supercritical carbon dioxide
Wang, Yunlong,Suo, Quanling,Han, Limin,Guo, Linlin,Wang, Yaqi,Li, Fawang
, p. 1918 - 1925 (2018/03/12)
An efficient protocol for the synthesis of unsymmetrical 1,3-diynes was developed using supercritical carbon dioxide (ScCO2) as the solvent. The direct coupling of two different terminal alkynes is catalysed by a bimetallic catalyst, CuCl2·2H2O/Pd(NH3)4Cl2·H2O, in the presence of the base tetramethylethylenediamine (TMEDA) and O2. In pure ScCO2, our bimetallic catalytic system maintains high activity over a wide substrate scope to provide unsymmetrical 1,3-diynes in good to excellent yields. In the proposed reaction mechanism, the synergistic cooperation between copper(II) and palladium(II) centres is responsible for the superior selectivity of the cross-coupling.
A Traceless Tether Strategy for Achieving Formal Intermolecular Hexadehydro-Diels-Alder Reactions
Smela, Merrick Pierson,Hoye, Thomas R.
, p. 5502 - 5505 (2018/09/12)
A synthetic strategy formally equivalent to an intermolecular hexadehydro-Diels-Alder (HDDA) reaction is described. Sulfur-based linkers were designed and constructed by joining terminal alkynes or diynes using alkyne thiolate chemistry. The resulting tetraynes and triynes successfully underwent HDDA cyclization and benzyne trapping. Linker removal by reductive desulfurization was uneventful. The strategy was also found suitable for the tetradehydro-Diels-Alder (TDDA) reaction.
