13305-02-7Relevant articles and documents
Novel finding of the effect of triple bond on the photochemical cis-trans isomerization of C=C double bond
Sakakibara, Hirokazu,Ikegami, Masashi,Isagawa, Kakuzo,Tojo, Sachiko,Majima, Tetsuro,Arai, Tatsuo
, p. 1050 - 1051 (2001)
Both cis- and trans-1,2-bis(phenylethynyl)ethenes (1) gave fluorescence emission with considerably high quantum yield and intersystem crossing to the triplet state which underwent cis-trans isomerization. On the basis of the results, a novel potential energy surface of isomerization of 1 was proposed.
Convenient one-pot synthesis of functionalized unsymmetrical (Z) or (E)-enediynes from (Z) or (E)-1,2-dichloroethylene. An efficient route to (Z,Z,Z) and (Z,E,Z)-trienes
Alami, Mouad,Crousse, Benoit,Linstrumelle, Gerard
, p. 3543 - 3544 (1994)
A variety of functionalized unsymmetrical (Z) or (E)-enediynes 1 and 2 are stereospecifically prepared in good overall yield by a simple straightforward one-pot procedure from (Z) or (E)-1,2-dichloroethylene and 1-alkynes. Zinc reduction of 1 and 2 leads
STEREOSPECIFIC SYNTHESES OF CIS- AND TRANS-1,6-BISTRIMETHYLSILYL-HEX-3-ENE-1,5-DIYNE
Vollhardt, K. Peter C.,Winn, Libbie S.
, p. 709 - 712 (1985)
Stereospecific syntheses of the title compounds were achieved via the palladium-catalyzed bisethynylation of the vicinal dichloroethenes.
Photochemistry of linear-shaped phenylacetylenyl- and (phenylacetylenyl) phenylacetylenyl-substituted aromatic enediynes
Sugiyama, Yoko,Shinohara, Yoshihiro,Momotake, Atsuya,Takahashi, Kayori,Kanna, Yoko,Nishimura, Yoshinobu,Arai, Tatsuo
scheme or table, p. 10929 - 10935 (2011/02/17)
The series of linear-shaped phenylacetylenyl- and (phenylacetylenyl) phenylacetylenyl-substituted aromatic enediynes 1-3 were synthesized as pure trans and cis isomers and their photochemistry explored. With expansion of the π-electron system, the absorpt
A p-benzyne to m-benzyne conversion through a 1,2-shift of a phenyl group. Completion of the benzyne cascade
Polishchuk, Alexei L.,Bartlett, Kevin L.,Friedman, Lee A.,Jones Jr., Maitland
, p. 798 - 806 (2007/10/03)
Pyrolysis of 1,6-diphenylhexa-1,5-diyne-cis-3-ene at 800-1000 °C leads to a mixture of 1- and 2-phenylbiphenylene, along with triphenylene. Formation of the two biphenylenes is taken as strong evidence of the rearrangement of a p-benzyne into a m-benzyne through a shift of one of the phenyl groups. Copyright
A direct route to conjugated enediynes from dipropargylic sulfones by a modified one-flask Ramberg-Baecklund reaction
Cao, Xiaoping,Yang, Yuying,Wang, Xiaolong
, p. 2485 - 2489 (2007/10/03)
The reaction of dipropargylic sulfones with dibromodifluoromethane in the presence of alumina-supported KOH in dichloromethane solution results in facile rearrangement affording the corresponding conjugated linear and cyclic enediynes in good yields. This result shows that the direct transformation of a- and a′-hydrogen bearing sulfones assembles enediyne units without resorting to the prior preparation of the a-halo sulfone precursors in a separate step.
A direct and stereocontrolled route to conjugated enediynes
Jones, Graham B.,Wright, Justin M.,Plourde, Gary W.,Hynd, George,Huber, Robert S.,Mathews, Jude E.
, p. 1937 - 1944 (2007/10/03)
A unified synthetic route to 3-hex-en-1,5-diynes, a key building block found in many of the enediyne antitumor agents and designed materials, was developed. The method, which relies on a carbenoid coupling-elimination strategy is tolerant of a wide range of functionalities, and was applied to the synthesis of a variety of linear and cyclic enediynes. Reaction parameters can be adjusted to control stereoselectivity of the process, producing linear enediynes from 1:12 to >100:1 E:Z ratio, and in the case of cyclic enediynes, giving the exclusively Z C-9, C-10, or C-11 products. Key features of the process are the ready availability of precursors and the mildness and efficiency of the reaction. Application of the process in the design of materials precursors and preparation of enediyne antitumor agents are presented.
Direct conversion of dipropargylic sulfones into (E)- and (Z)-Hex-3-ene-1,5-diynes by a modified one-flask Ramberg-Backlund reaction
Cao,Chan,Chow
, p. 1049 - 1052 (2007/10/03)
(E)- and (Z)-enediynes 7 are readily synthesized in good yields from a one-pot modified Ramberg-Backlund reaction from dipropargylic sulfones 5.
Process for synthesizing enediynes
-
, (2008/06/13)
A process for synthesizing enediynes is provided. Specifically, the formed enediynes contain a hex-3-ene-1,5-diynyl group. Production of the enediynes involves adding a base to a propargylic halide in the presence of a chelating agent, which causes a carb
Carbene-carbene interconversion between 1- and 3-phenyl-2-propynylidenes
Noro, Masaki,Masuda, Takeshi,Ichimura, Andrew S.,Koga, Noboru,Iwamura, Hiizu
, p. 6179 - 6190 (2007/10/02)
1-Phenyl-3-diazopropyne (1d) and 3-phenyl-3-diazopropyne (2d) were prepared and photolyzed under various conditions. In ethanol at ambient temperatures, both 1d and 2d gave a 1:10 ± 1 mixture of 1-phenyl-3-ethoxypropyne (3) and 3-phenyl-3-ethoxypropyne (4). The photolyses of matrix-isolated 1d and 2d at cryogenic temperatures were followed by EPR, IR, and UV-visible spectroscopy. EPR experiments in 2-methyltetrahydrofuran (MTHF), isopentane, and ethanol-d6 matrices at 9 K showed spectra due to a mixture of the corresponding triplet carbenes 1c (D/hc = 0.543 and |E/hc| = 0.003 cm-1) and 2c (D/hc = 0.526 and |E/hc| = 0.010 cm-1). The ratio of the generated carbenes carried the memory of the starting diazo compounds; 1c and 2c were produced mainly from 1d and 2d, respectively. Carbene 2c isomerized to 1c at 70-90 K in MTHF and ethanol-d6 and at 44-68 K in isopentane, indicating that 1c was thermodynamically more stable than 2c on the triplet ground-state potential energy surface. IR and UV-visible absorption experiments employing various media (argon, isopentane, N2, CO/Ar, O2/N2, and O2/Ar) revealed that the photolysis of 2d afforded mostly absorptions due to 2c. Photolysis of 1d produced similar spectra, due mainly to 2c, together with weak absorptions due to 1c. The different results observed in EPR and IR experiments were explained by the difference in the matrices in which the diazo groups were photolyzed. Calculations at the ab initio MP2/DZV(d) level of theory showed that the triplet ground state of 1c was more thermodynamically stable than 2c by 1.41 kcal/mol, in agreement with the experimental results. The situation is reversed in the singlet manifold, where 2c was computed to be much lower in energy than 1c. The energy differences (ΔEST) between the singlet and triplet states were computed to be 15.7 and 11.0 kcal/mol for 1c and 2c, respectively, with the DZV(d) basis set.
