4551-51-3Relevant articles and documents
Fabricating nickel phyllosilicate-like nanosheets to prepare a defect-rich catalyst for the one-pot conversion of lignin into hydrocarbons under mild conditions
Cao, Meifang,Chen, Bo,He, Chengzhi,Ouyang, Xinping,Qian, Yong,Qiu, Xueqing
supporting information, p. 846 - 857 (2022/02/09)
The one-pot conversion of lignin biomass into high-grade hydrocarbon biofuels via catalytic hydrodeoxygenation (HDO) holds significant promise for renewable energy. A great challenge for this route involves developing efficient non-noble metal catalysts to obtain a high yield of hydrocarbons under relatively mild conditions. Herein, a high-performance catalyst has been prepared via the in situ reduction of Ni phyllosilicate-like nanosheets (Ni-PS) synthesized by a reduction-oxidation strategy at room temperature. The Ni-PS precursors are partly converted into Ni0 nanoparticles by in situ reduction and the rest remain as supports. The Si-containing supports are found to have strong interactions with the nickel species, hindering the aggregation of Ni0 particles and minimizing the Ni0 particle size. The catalyst contains abundant surface defects, weak Lewis acid sites and highly dispersed Ni0 particles. The catalyst exhibits excellent catalytic activity towards the depolymerization and HDO of the lignin model compound, 2-phenylethyl phenyl ether (PPE), and the enzymatic hydrolysis of lignin under mild conditions, with 98.3% cycloalkane yield for the HDO of PPE under 3 MPa H2 pressure at 160 °C and 40.4% hydrocarbon yield for that of lignin under 3 MPa H2 pressure at 240 °C, and its catalytic activity can compete with reported noble metal catalysts.
Polyspiranes, 16. - Cascade Rearrangements, 11. - Synthesis, Structure, Conformation, and Dynamics of Heptacyclo1,5.05,9.09,13.013,17.017,21>tetracosane (Coronane)
Wehle, Detlef,Schormann, Norbert,Fitjer, Lutz
, p. 2171 - 2178 (2007/10/02)
Coronane (2) was synthesized by addition of allylmagnesium bromide to ketone 7, rearrangement of the resulting homoallyl alcohol 8a to diene 9, hydrozirconization of 9 followed by bromination to give 11, and finally radical cyclization of 11.A direct cyclization of 9 using tri(n-butyl)tin hydride failed. 2 is all-cis-configurated, adopts a chair conformation in the crystal state and in solution and exhibits an extremely low barrier of inversion (ΔG(excit.)173 /= 8.6 kcal/mol).
REACTION OF cis-BICYCLONONA-3,7-DIENE WITH IODINE. SYNTHESIS OF TRICYCLO3,7>NONA-4,8-DIENE (BREXA-4,8-DIENE)
Lukovskaya, E. V.,Bobyleva, A. A.,Pekhk, T. I.,Dubitskaya, N. F.,Petrushenkova, I. A.,Belikova, N. A.
, p. 1311 - 1317 (2007/10/02)
The reaction of iodine with cis-bicyclonona-3,7-diene is accompanied by regioselective and stereoselective transannular cyclization with the formation of endo-4,exo-8-diiodobrexane.Methods were developed for the production of endo-9-iodobrex-4-ene and brexa-4,8-diene with yields of 26 and 20percent respectively.The mechanism of transannular cyclization is discussed.
TERMINATION REACTIONS OF C5-C12 CYCLOALKYL RADICALS AND CARBENES
Wojnarovits, Laszlo
, p. 1449 - 1452 (2007/10/02)
Reactions of C5-C12 cycloalkyl radicals and carbenes produced during radiolysis, vacuum-u.v. photolysis, and decomposition of cycloalkanone p-tosylhydrazones were investigated.The disproportionation to combination ratios of radicals are ca. 1 and agree with the ratios of linear secondary radicals.The disproportionation smaller cycloalkyl radicals yields cis-cycloalkenes and cycloalkanes; from C9 and C10 cis- and trans-cycloalkenes and cycloalkanes and from C11 and C12 trans-cycloalkenes and cycloalkanes are produced.Both atoms of H2 given off in the elimination reaction from excited cycloalkane molecules orginate from the same carbon atom and in this process carbenes are formed.Rearrangement of small (C5, C6) and large (C11, C12) cycloalkylcarbenes in the solvent of the given cycloalkane occurs by 1,2-hydrogen migration.C7-C10 carbenes rearrange both by hydrogen atom migration and transannular insertion.
FORMATION OF SOME BICYCLIC SYSTEMS BY RADICAL RING-CLOSURE
Beckwith, Athelstan L. J.,Phillipou, George,Serelis, Algirdas K.
, p. 2811 - 2814 (2007/10/02)
The rates and stereochemistry of ring closure of the radicals (2), (9), (10), and (16) have been determined and rationalised.
