表面有機金属化学によってシリカに支えられた明確に定義されたモリブデンオキシアルキル複合体:高度に活性なオレフィンメタテシス前触媒
Nicolas Merle1, Frédéric Le Quéméner1, Yassine Bouhoute1
1Laboratoire de Chimie, Catalyse, Polymères et Procédés, UMR 5265 CNRS/ESCPE-Lyon/UCBL, ESCPE Lyon, F-308-43, Boulevard du 11 Novembre 1918, F-69616 Villeurbanne Cedex, France.
Journal of the American Chemical Society
|February 7, 2017
まとめ
シリカを支える新しいモリブデンオキシアルキル種が合成され,特徴づけられました. この新しい触媒はプロペンの自己メタテシスで例外的な活性を示し,既存の触媒を上回っています.
科学分野:
- カタリシス
- 有機金属化学
- 材料科学
背景:
- 産業用オレフィンメタテシスは,サポートされた酸化モリブデン (MoO3/SiO2) 触媒に依存しています.
- 活性表面種を理解することは,触媒の改善に不可欠です.
研究 の 目的:
- 精確に定義されたシリカを支えるモリブデンオキシアルキル種を合成し,特徴づけること.
- プロペンの自己メタテシスにおけるその触媒的活動を評価する.
主な方法:
- 移植のための表面有機金属化学アプローチ.
- 元素解析,DRIFT,固体NMR,EXAFSスペクトロスコーピーを用いた特徴付け.
- プロペンの自己メタテシスの触媒試験
主要な成果:
- シリカを支えるモリブデンオキシアルキル種 (SiO-) MoO ((CH2tBu)) を成功裏に製造し,特徴づけました.
- 触媒は軽度な条件下でプロペンの自己転移で高い活性を示した (ターンオーバー数=25時間で90,000).
- イミドとオクソ類の原産物の触媒性能を上回った.
結論:
- 合成されたモリブデンオキシアルキル種はオレフィン転移の有望な活性部位である.
- この研究は,先進的なモリブデン支援触媒の開発の洞察を提供します.
関連する概念動画
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
13.2K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
13.2K
Hydroboration-Oxidation of Alkenes
11.9K
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
11.9K
Radical Oxidation of Allylic and Benzylic Alcohols
3.0K
Activated manganese(IV) oxide can selectively oxidize allylic and benzylic alcohols via a radical intermediate mechanism. Primary allylic alcohols are oxidized to aldehydes, while secondary allylic alcohols yield ketones. The redox reaction of potassium permanganate with an Mn(II) salt such as manganese sulfate (under either alkaline or acidic conditions), followed by thorough drying, yields the oxidizing agent: activated MnO2. While MnO2 is insoluble in the solvents used for the reaction, the...
3.0K
Properties of Organometallic Compounds
1.9K
Organometallic compounds are compounds that contain a carbon–metal bond. Carbon belongs to an organyl group like alkyl, aryl, allyl, or benzyl groups. The metal can be from Group I or Group II of the periodic table, a transition metal, or a semimetal.
1.9K
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
2.4K
The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.
2.4K
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
17.5K
Alkenes can be dihydroxylated using potassium permanganate. The method encompasses the reaction of an alkene with a cold, dilute solution of potassium permanganate under basic conditions to form a cis-diol along with a brown precipitate of manganese dioxide.
17.5K


