Synthesis of 1,2,3,5-oxathiadiazole 2-oxides from amidoximes and thionyl chloride and the mechanism of their thermally induced fragmentation and rearrangement to carbodiimides
A New Synthetic Protocol for the Preparation of Carbodiimides Using a Hypervalent Iodine(III) Reagent
作者:Yunyang Wei、Chenjie Zhu、Dan Xu
DOI:10.1055/s-0030-1258414
日期:2011.3
A new, simple, and efficient preparation of symmetrical and unsymmetrical carbodiimides from the corresponding thioureas via dehydrosulfurization using a hypervalent iodine(III) reagent is described. The oxidation afforded carbodiimides in excellent yields and high selectivity. A possible mechanism for the transformation is proposed. desulfurization - hypervalent iodine - oxidations - carbodiimides
A facile method for the preparation of carbodiimides from thioureas and (Boc) 2 O
作者:He Wu、Yan-Fang Sun、Chen Zhang、Chun-Bao Miao、Hai-Tao Yang
DOI:10.1016/j.tetlet.2018.01.025
日期:2018.2
A concise method for the preparation of carbodiimides from thioureas using di-tert-butyl dicarbonate [(Boc)2O] as the dehydrosulfurizative reagent has been developed. Using DMAP as the catalyst, a variety of symmetric and asymmetric 1,3-diaryl thioureas were converted into the corresponding carbodiimides efficiently in a short time.
strategy for the regioselective assembly of 2-aminoimidazole derivatives is herein described. Through a transition metal-free domino addition/cyclization process, the reactions of unsymmetrical carbodiimides with propargylic amines mediated by Cs2CO3 selectively afforded the corresponding polysubstituted 2-aminoimidazoles in moderate to good yields under very mild conditions. The regioselectivity was reversed
本文描述了2-氨基咪唑衍生物的区域选择性组装的方便的单步策略。通过无过渡金属的多米诺加成/环化过程,不对称碳二亚胺与Cs 2 CO 3介导的炔丙基胺的反应在非常温和的条件下以中等至良好的收率选择性地提供了相应的多取代的2-氨基咪唑。在较高温度下,在TEA存在下,区域选择性反转。所获得的2-(邻碘芳基)氨基咪唑可以容易地转化为2-(2-联苯基)氨基咪唑,2-(邻炔基苯基)氨基咪唑,苯并咪唑并[1,2- a ]咪唑和N-(咪唑-2-基)吲哚衍生物。
Synthesis of Phosphaguanidines by Hydrophosphination of Carbodiimides with Phosphine Boranes
作者:Carl A. Busacca、John A. Milligan、Eakkaphon Rattanangkool、Cyrus Ramavarapu、Anji Chen、Anjan K. Saha、Zhibin Li、Heewon Lee、Steven J. Geib、Guijun Wang、Chris H. Senanayake、Peter Wipf
DOI:10.1021/jo501841s
日期:2014.10.17
The direct addition of anionic secondary phosphine boranes to carbodiimides yields both chiral and achiral phosphaguanidine boranes, under ambient temperature conditions. An analogous preparation of menthol-derived phosphinite boranes is also described. These products can be deborinated to give the corresponding phosphines, and subsequently oxidized to give phosphine oxides. The robustness of this method was further demonstrated in the synthesis of structurally novel cyclic phosphaguanidines.
A New Approach to 1-Nitro-2,2-bis[alkyl- or arylamino]ethylenes: A New Synthesis of Ranitidine