25856-02-4Relevant academic research and scientific papers
Simultaneous observation of triplet and singlet cyclopentane-1,3-diyl diradicals in the intersystem crossing process
Mizuno, Takemi,Abe, Manabu,Ikeda, Noriaki
, p. 1700 - 1706 (2015)
Intersystem crossing is an important chemical process. In this study, the rate constant of intersystem crossing, kISC ~3×107s-1, for cyclopentane-1,3-diyl diradicals was unequivocally determined by the simultaneous observation of the decay process of the
An effective preparation of both 1,3-diketones and nitriles from alkynones with oximes as hydroxide sources
Chen, Pei,Zhang, Qian-Qian,Guo, Jia,Chen, Lu-Lu,Wang, Yan-Bo,Zhang, Xiao
, p. 6958 - 6966 (2018/10/02)
An effective phosphine-catalyzed protocol has been established for the syntheses of 1,3-diketones and nitriles from alkynones with oximes as hydroxide surrogates. This method features the use of a phosphine catalyst, compatibility with various functional groups and ambient temperature, which makes this approach very practical. A plausible mechanism was proposed.
2-Hydroxylation of 1,3-Diketones with Atmospheric Oxygen
Li, Zheng,Li, Tianpeng,Li, Jiasheng,He, Lili,Jia, Xianggui,Yang, Jingya
supporting information, p. 2863 - 2865 (2015/12/18)
An efficient method for the 2-hydroxylation of 1,3-diketones by using atmospheric oxygen as an oxidant under transition-metal-free condition is described. The protocol has the advantages of using an inexpensive and stable oxidant, producing high yields, and requiring ecofriendly conditions.
Transition-metal-free formal decarboxylative coupling of ?±-oxocarboxylates with ?±-bromoketones under neutral conditions: A simple access to 1,3-diketones
He, Zhen,Qi, Xiaotian,Li, Shiqing,Zhao, Yinsong,Gao, Ge,Lan, Yu,Wu, Yiwei,Lan, Jingbo,You, Jingsong
, p. 855 - 859 (2015/02/05)
A transition-metal-free formal decarboxylative coupling reaction between ?±-oxocarboxylates and ?±-bromoketones to synthesize 1,3-diketone derivatives is presented. In this reaction, a broad scope of substrates can be employed, and neither a metal-based reagent nor an additional base is required. DFT calculations reveal that this reaction proceeds through a coupling followed by decarboxylation mechanism and the ?±-bromoketone unprecedentedly serves as a nucleophile under neutral conditions. The rate-determining step is an unusual hydrogen-bond-assisted enolate formation by thermolysis.
Asymmetric transfer hydrogenation of unsymmetrical benzils
Zhang, Hao,Feng, Dandan,Sheng, Haibo,Ma, Xuebing,Wan, Jinwei,Tang, Qian
, p. 6417 - 6423 (2014/02/14)
In this paper, the asymmetric transfer hydrogenation of unsymmetrical benzils with m, p-substituents was conducted with a substrate/catalyst molar ratio of 100 at 40°C for 24 h to produce (S,S)-hydrobenzoins in good yields (76.2% to 97.1%) with high diastereomeric (syn/anti = 10.8 to 29.7/1) and enantiomeric purities (86.1%ee syn to 98.9%ee syn). Unfortunately, the unsymmetrical benzils with the o-substituents such as electron-donating (R = CH3, OCH3) and electron-withdrawing groups (R = F, Cl, CF3) resulted in poor yields (0% to 31.2%), even at 40°C for 72 h. These products had inefficient diastereoselectivities (syn/anti = 1.5 to 5.0/1) caused by steric effects. Furthermore, the results of a dynamic-kinetic study were used to propose a plausible reaction pathway of unsymmetrical benzil using 3-methoxy-1,2-diphenyl ethanedione as an example.
Process for preparing vinyl substituted beta-diketones
-
Page/Page column 9, (2008/06/13)
A process for preparing vinyl substituted beta-diketones includes reacting a halogen-containing beta-diketone with an olefin in a reaction zone under Heck coupling reaction conditions in the presence of a catalyst, a base, and an organic phosphine to provide a vinyl substituted beta-diketone product.
Synthesis of vinyl-substituted β-diketones for polymerizable metal complexes
Southard, Glen E.,Murray, George M.
, p. 9036 - 9039 (2007/10/03)
Polymerizable β-diketones for application to metal ion coordination have been prepared and characterized. Bromine-substituted β-diketones were synthesized under Claisen-Schmidt-type condensation conditions. Vinyl groups were substituted for the halide by
