Reductive Deuteration of Acyl Chlorides for the Synthesis of α,α-Dideuterio Alcohols Using SmI2 and D2O.

The synthesis of α,α-dideuterio alcohols has been achieved via single electron transfer reductive deuteration of acyl chlorides using SmI2 and D2O. This method is distinguished by its remarkable functional group tolerance and exquisite deuterium incorporation, which has also been applied to the synthesis of valuable deuterated agrochemicals and their building blocks.

One-Pot Sequential Hydrogen Isotope Exchange/Reductive Deuteration for the Preparation of α,ß-Deuterated Alcohols using Deuterium Oxide.

An efficient one-pot sequential hydrogen isotope exchange (HIE)/reductive deuteration approach was developed for the preparation of α,ß-deuterated alcohols using ketones as the precursors. The HIE step can also be used for the synthesis of α-deuterated ketones. This method has been applied in the synthesis of four deuterated drug and MS internal standards.

Acyl fluorides as direct precursors to fluoride ketyl radicals: reductive deuteration using SmI2 and D2O.

A highly chemoselective reductive deuteration of acyl fluorides to provide α,α-dideuterio alcohols with exquisite levels of deuterium incorporation was developed using SmI2 and D2O as the deuterium source. This method introduces acyl fluorides as attractive radical precursors for the generation of reactive acyl-type fluoride ketyls that should find widespread application in many synthetic strategies involving single electron transfer processes.

Synthesis of α-Deuterated Primary Amines via Reductive Deuteration of Oximes Using D2O as a Deuterium Source.

Selective introduction of the deuterium atom into the α-position of amines is important for the development of all types of novel deuterated drugs and agrochemicals due to the pervasive presence of amines. In this study, we report the first general single-electron-transfer reductive deuteration of both ketoximes and aldoximes using SmI2 as an electron donor and D2O as a deuterium source for the synthesis of α-deuterated primary amines with excellent levels of deuterium incorporations (>95% [D]). This protocol exhibits excellent chemoselectivity and tolerates a variety of functional groups. The potential application of this new method was showcased in the synthesis of deuterated drugs, such as rimantadine-d4, the tebufenpyrad analogue, derivatives of nabumetone and pregnenolone, and a series of building blocks for the rapid and general assembly of deuterated drugs and pesticides.

Pentafluorophenyl Esters: Highly Chemoselective Ketyl Precursors for the Synthesis of α,α-Dideuterio Alcohols Using SmI2 and D2O as a Deuterium Source.

We report the first highly chemoselective synthesis of α,α-dideuterio alcohols with exquisite incorporation of deuterium (>98% [D2]) using pentafluorophenyl esters as ketyl radical precursors, SmI2 as a mild reducing agent, and D2O as the deuterium source. This system tolerates a variety of functional groups, offering rapid entry to valuable α,α-dideuterated alcohol building blocks. More generally, this report introduces pentafluorophenyl esters as the most reactive O-ketyl precursors reported to date.

Selective C-N σ Bond Cleavage in Azetidinyl Amides under Transition Metal-Free Conditions.

Functionalization of amide bond via the cleavage of a non-carbonyl, C-N σ bond remains under-investigated. In this work, a transition-metal-free single-electron transfer reaction has been developed for the C-N σ bond cleavage of N-acylazetidines using the electride derived from sodium dispersions and 15-crown-5. Of note, less strained cyclic amides and acyclic amides are stable under the reaction conditions, which features the excellent chemoselectivity of the reaction. This method is amenable to a range of unhindered and sterically encumbered azetidinyl amides.

Mesoporous activated carbon from starch for superior rapid pesticides removal.

Pesticides contamination of water has caused considerable concern due to the potential hazard to human health. For the first time, mesoporous activated carbon from starch (ACS) was applied to remove pesticides from water. ACS could remove 11 pesticides rapidly (shake five times). The adsorption rates of ACS (>80%) for the 11 pesticides were higher than those of other adsorbents, including commercial activated carbon (AC), graphitised carbon black (GCB), C18, and primary secondary amine adsorbent (PSA). The mechanisms of the adsorption process for pyraclostrobin were also investigated. The pseudo-second-order model could better describe the adsorption for pyraclostrobin (R2 = 0.99950). Langmuir model gave the best fit for the isotherm data (R2 = 0.99899). Our findings demonstrate that oxygen-containing functional groups, N atom and π-bonding network of benzene promoted the adsorption. The adsorption efficiency of the ACS for 11 pesticides was still over 80% after five cycles.