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A conceptually novel sulfoxonium metathesis reaction between TMSOI and cost-effective DMSO-d 6 is developed for the efficient generation of a new trideuteromethylation reagent TDMSOI. The new reagent TDMSOI is produced highly efficiently by simply heating a mixture of TMSOI and DMSO-d 6 and directly used for subsequent trideuteromethylation in a “one-pot” operation. The preparative power of the new versatile reagent and the “one-pot” protocol is demonstrated by its use to install the −CD3 moiety into broad functionalities including phenols, thiophenols, acidic amines, and enolizable methylene units in high yield and at a useful level of deuteration (>87% D).

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We have identified a switchable Prins cyclization process to form indoline‐fused tetrahydrofurans and indole‐fused oxepanes by applying different types of aldehydes under two sets of optimized conditions. Significantly, a novel Prins reaction mechanism involving an oxonium‐mediated rearrangement in the formation of five‐membered cyclic ethers is realized for the first time.magnified image

An efficient method has been developed for the synthesis of deuterated benzoins from two molecules of aldehydes under the catalysis of N-heterocyclic carbene by using D2O as the deuterium source, providing the products with deuterium selectively incorporated at the α-position of ketone group. The method features simple operation and mild reaction conditions, and a variety of aromatic aldehyde substrates could afford products with high deuterium incorporation. Keywords deuteration; deuteroxide; benzoin condensation; N-heterocyclic carbene; organocatalysis 氘( 2 H 或者 D)是氢( 1 H)安全、稳定的同位素, 氘代 化合物具有广泛的用途, 可用于核磁共振分析、反应机 理研究、材料科学和药物研发 [1][2][3][4] . 2017 年, 氘代丁苯那 嗪(SD-809)作为第一个氘代药物被美国食品药品监督管 理局(FDA)批准上市 [5] . 氘代分子的制备主要有合成砌 块法、化学转化法和氢-氘交换方法(hydrogen deuterium exchange, HDE)等 [1][2][3][4]6] . 与传统的源于氘代合成砌块的 多步合成方法不同, HDE 反应不需要稀缺或昂贵的原 料, 一般采用常见的氘代溶剂或市售氘气作为氘源, 在 催化剂作用下发生反应, 简便易操作. 从机理上讲, HDE 属于一个可逆过程, 通过活化特定的 C-H 键达到 H-D 交换的目的. 化学家们已经成功开发了多种 HDE 反应 [7][8][9][10][11][12][13][14][15] , 经典的 HDE 方法使用酸/碱 [7] 或过渡金属 [8] 催 化, 通常导致非选择性的多位点氘代. 最近的研究主要 集中在芳香族 C(sp 2 )-H [9] 、未活化的脂肪族 C(sp 3 )-H [10] 、与杂原子相邻的 C-H 键 [11] 、糖 [12] 、氨基酸 [13] 、 烯烃 [14] 和醛 [15] 的位点选择性氘代.