556-82-1Relevant articles and documents
Configurational Stability of a Cyclopropyl Grignard Reagent Containing a Metalated 2-Hydroxymethyl Group
Richey, Herman G.,Moses, L. Meredith
, p. 4013 - 4017 (1983)
Mixtures of cis- and trans-2-bromo-3-(hydroxymethyl)-1,1-dimethylcyclopropane were treated with methylmagnesium bromide to metalate the hydroxyl groups and then with magnesium to form metalated Grignard reagents.The compositions of products obtained upon hydrolysis with D2O indicated that the metalated Grignard reagents in refluxing diethyl ether did not undergo significant cis-trans isomerization.This work provides an example of the configurational stability of a cyclopropyl Grignard reagent with a secondary rather than a tertiary α-carbon.Because of these resultswith cyclopropyl Grignard reagents containing a metalated hydroxyl group, prior observations on additions of allylic Grignard reagents to 3-(hydroxymethyl)cyclopropenes only of products resulting from a cis relationship of magnesium and hydroxymethyl must be due to the stereochemistry of the addition process rather than to a subsequent isomerization.
Reaction of Methylbutenol with Hydroxyl Radical: Mechanism and Atmospheric Implications
Rudich, Yinon,Talukdar, Ranajit,Burkholder, James B.,Ravishankara, A. R.
, p. 12188 - 12194 (1995)
The tropospheric fate of 2-methyl-3-buten-2-ol (methylbutenol, MBO), a recently identified emission by vegetation, was investigated by measuring its UV absorption cross sections (210-300 nm) and the rate coefficient for its reaction with hydroxyl free radicals.UV absorption cross sections were found to be too small for photolysis to be an important removal pathway for MBO in the troposphere.The rate constant applicable under tropospheric conditions for the reaction of OH with MBO was determined to be k=(8.2 +/- 1.2) * 10-12 e((610 +/- 50)/T) cm3 molecule-1 s-1.The OH reaction proceeds mainly via addition of the OH to the double bond in MBO.In the absence of O2, about 15-20percent of the adducts eliminate the alcohol-OH group.However, O2 can scavenge the adduct before it decomposes at T 300 K.This mechanism was confirmed by measuring the rate coefficients for the reactions of OD and 18OH and determining the rate coefficient for the OH reaction in the presence of 7-13 Torr of O2 and in SF6 buffer gas.The elimination of alcohol-OH group was substantiated by observing OH production in the reactions of 18OH and OD.The obtained OH reaction rate coefficient suggests that the primary daytime loss of MBO in the troposphere is via its reaction with OH.
Ir nanoclusters confined within hollow MIL-101(Fe) for selective hydrogenation of α,β-unsaturated aldehyde
Chen, Yurong,Li, Guangqin,Li, Yinle,Liu, Qian,Liu, Qinghua,Liu, Qinglin,Su, Hui
supporting information, (2021/08/13)
Although the selective hydrogenation of α,β-unsaturated aldehyde to unsaturated alcohol (UOL) is an extremely important transformation, it is still a great challenge to achieve high selectivity to UOL due to thermodynamic favoring of the C[dbnd]C hydrogenation over the C[dbnd]O hydrogenation. Herein, we report that iridium nanoclusters (Ir NCs) confined within hollow MIL-101(Fe) expresses satisfied reaction activity (93.9%) and high selectivity (96.2%) for the hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL) under 1 bar H2 atmosphere and room temperature. The unique hollow structure of MIL-101(Fe) benefits for the fast transport of reactant, ensuring the comparable reaction activity and better recyclability of Ir@MIL-101(Fe) than the counterparts which Ir NCs were on the surface of MIL-101(Fe). Furthermore, The X-ray photoelectron spectroscopy data indicates the electropositive Ir NCs, owing to the electron transfer from Ir to MIL-101(Fe), can interact with oxygen lone pairs, and Fourier transform infrared spectrum shows the Lewis acid sites in MIL-101(Fe) can strongly interact with C[dbnd]O bond, which contributes to a high selectivity for COL. This work suggests the considerable potential of synergetic effect between hollow MOFs and metal nanoclusters for selective hydrogenation reactions.
Nickel-Catalyzed Asymmetric Reductive 1,2-Carboamination of Unactivated Alkenes
He, Jun,Xue, Yuhang,Han, Bo,Zhang, Chunzhu,Wang, You,Zhu, Shaolin
supporting information, p. 2328 - 2332 (2020/01/08)
Starting from diverse alkene-tethered aryl iodides and O-benzoyl-hydroxylamines, the enantioselective reductive cross-electrophilic 1,2-carboamination of unactivated alkenes was achieved using a chiral pyrox/nickel complex as the catalyst. This mild, modular, and practical protocol provides rapid access to a variety of β-chiral amines with an enantioenriched aryl-substituted quaternary carbon center in good yields and with excellent enantioselectivities. This process reveals a complementary regioselectivity when compared to Pd and Cu catalysis.
