10.1021/jo981533h
The research focuses on the development of a convenient one-pot synthesis method for 1,4-dihalobutadienes from alkynes via titanacyclopentadienes, which are significant as precursors for various metalloles containing main group elements. The study aims to overcome the limitations of existing synthetic routes, particularly in the preparation of exocyclic and 2,3-unsubstituted-1,4-dihalobutadienes, which are crucial for the synthesis of bicyclic and 3,4-unsubstituted metalloles. The researchers successfully developed a method that involves the preparation and halogenolysis of titanacyclopentadienes derived from alkynes with a divalent titanium complex, (η2propene)Ti(O-i-Pr)2, which is prepared in situ from Ti(O-i-Pr)4 and i-PrMgCl. The process yields 1,4-dihalobutadienes in good to excellent yields without the need for additives like CuCl, and is more cost-effective compared to the zirconacyclopentadiene route. The synthesized 1,4-dihalobutadienes were further transformed into a series of silole derivatives, demonstrating the synthetic utility of the developed methodology. Key chemicals used in the process include alkynes, Ti(O-i-Pr)4, i-PrMgCl, iodine, bromine, and Si(OMe)4.
10.1002/anie.200500443
The research explores a new method for the functionalization of arenes through the addition of nucleophiles to arynes. The purpose of this study is to develop a general procedure for the selective addition of magnesiated thiols and amines to arynes, resulting in the formation of functionalized aryl magnesium species that can be trapped by various electrophiles. Key chemicals used in this research include thiophenol, various substituted thiophenolates (such as 2b-d), magnesium reagents like iPrMgCl, and electrophiles such as iodine, DMF, acid chlorides, and aldehydes. The study concludes that the addition of these nucleophiles to arynes is facilitated by the high reactivity of the arynes, leading to the formation of useful aryl magnesium intermediates that can be efficiently trapped to yield thioethers and arylamines with good yields. The procedure demonstrates excellent functional-group compatibility and regioselectivity, and the researchers are currently exploring extensions using other nucleophiles.
10.1039/c3cc41703d
The research aims to investigate the coordination preferences of lithium (Li), magnesium (Mg), and copper (Cu) cations with nitriles, focusing on whether these metals preferentially coordinate to the nitrogen (N-metalation) or carbon (C-metalation) atoms in nitriles. The study used a series of metalated arylacetonitriles and cyclohexanecarbonitriles to analyze the influence of the carbon scaffold and the nature of the metal on the preference for N- or C-metalation through 13C NMR analyses. The chemicals used in the process include phenylacetonitrile, cyclohexanecarbonitrile, and various metalating agents such as BuLi, i-PrMgCl, CuI, and Me2CuLi. The research concluded that lithium and magnesium preferentially coordinate to the nitrile nitrogen in arylacetonitriles, while copper favors C-metalation. The study also found that the carbon scaffold can significantly influence the coordination preferences, with magnesiated nitriles showing a preference for N-metalation with arylacetonitriles and C-metalation with cyclohexanecarbonitrile. These findings underscore the complex nature of metalated nitriles and their structural identity, which is intimately tied to the metal cation and the nature of the substituents on the nucleophilic carbon.
C, 
F+, 
F
