[EN] SYNTHESIS OF DEUTERATED ALDEHYDES<br/>[FR] SYNTHÈSE D'ALDÉHYDES DEUTÉRÉS
申请人:UNIV ARIZONA
公开号:WO2021045879A1
公开(公告)日:2021-03-11
Described are methods for preparing a deuterated aldehyde using N-heterocyclic carbene catalysts in a solvent comprising D2O. The methods may be used to convert a wide variety of aldehydes (e.g., aryl, alkyl, or alkenyl aldehydes) to C-1 deuterated aldehydes under mild reaction conditions without functionality manipulation.
The selectiveoxidation of alcohol-d1 to prepare aldehyde-d1 was newly developed by means of NaBD4 reduction/activated MnO2 oxidation. Various aldehyde-d1 derivatives including aromatic and unsaturated aldehyde-d1 can be prepared with a high deuterium incorporation ratio (up to 98% D). Halogens (chloride, bromide, and iodide), alkene, alkyne, ester, nitro, and cyano groups in the substrates are tolerated
N-Heterocyclic Carbene Catalyzed Deuteration of Aldehydes in D2O
作者:Yoshinari Sawama、Yuya Miki、Hironao Sajiki
DOI:10.1055/s-0040-1707993
日期:2020.4
An N-heterocycliccarbene (NHC)-catalyzed direct deuteration of aldehydes in a mixed solvent of deuterium oxide (D2O) and cyclopentyl methyl ether was established. The present deuteration is possibly initiated by the formation of a Breslow intermediate from the aldehyde and the NHC, with subsequent trapping by D2O providing the monodeuterated aldehyde.
Rate and Equilibrium Constants for the Addition of N-Heterocyclic Carbenes into Benzaldehydes: A Remarkable 2-Substituent Effect
作者:Christopher J. Collett、Richard S. Massey、James E. Taylor、Oliver R. Maguire、AnnMarie C. O'Donoghue、Andrew D. Smith
DOI:10.1002/anie.201501840
日期:2015.6.1
Rate and equilibriumconstants for the reaction between N‐aryl triazolium N‐heterocyclic carbene (NHC) precatalysts and substituted benzaldehyde derivatives to form 3‐(hydroxybenzyl)azolium adducts under both catalytic and stoichiometric conditions have been measured. Kinetic analysis and reaction profile fitting of both the forward and reverse reactions, plus onwards reaction to the Breslow intermediate
Bis(oxazoline)–ligand-mediated asymmetric [2,3]-Wittig rearrangement of benzyl ethers: reaction mechanism based on the hydrogen/deuterium exchange effect
asymmetric [2,3]-Wittig rearrangement of allyl benzyl ether in the presence of a bis(oxazoline) chiral ligand [(S,S)-Box–tBu] by comparing the reaction of both enantiomers of monodeuterated benzyl ether 1a–d. As a result, we found that chirality was induced via enantioselective deprotonation followed by efficient chirality transfer of the resulting chiral benzyl carbanion with the inversion of stereochemistry
我们通过比较反应,研究了在双(恶唑啉)手性配体[(S,S)-Box- t Bu]存在下烯丙基苄基醚的不对称[2,3] -Wittig重排中的手性诱导机理。氘代苄基醚1a - d的两种对映体的组成。结果,我们发现手性是通过对映选择性去质子化诱导的,然后通过立体化学的反转有效地手性转移所得的手性苄基碳负离子。揭示了手性配体促进选择性去质子化并防止手性碳负离子消旋化。此外,我们检查了o的影响苯环上的-甲氧基取代基。