Ruthenium-Catalyzed meta-Selective C—H Bromination

نویسندگان

  • Christopher J Teskey
  • Andrew Y W Lui
  • Michael F Greaney
چکیده

The first example of a transition-metal-catalyzed, meta-selective C-H bromination procedure is reported. In the presence of catalytic [{Ru(p-cymene)Cl2 }2 ], tetrabutylammonium tribromide can be used to functionalize the meta C-H bond of 2-phenylpyridine derivatives, thus affording difficult to access products which are highly predisposed to further derivatization. We demonstrate this utility with one-pot bromination/arylation and bromination/alkenylation procedures to deliver meta-arylated and meta-alkenylated products, respectively, in a single step.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Iridium-catalyzed borylation of thiophenes: versatile, synthetic elaboration founded on selective C-H functionalization.

Iridium-catalyzed borylation has been applied to various substituted thiophenes to synthesize poly-functionalized thiophenes in good to excellent yields. Apart from common functionalities compatible with iridium-catalyzed borylations, additional functional group tolerance to acyl (COMe), and trimethylsilyl (TMS) groups was also observed. High regioselectivities were observed in borylation of 3-...

متن کامل

Selective Mono Bromination of 1,4-Dihydropyridines

2-monobromomethyl 1,4-dihydropyridines is selectively synthesized by bromination of the parent compound by 1.1 equivalents of pyridinium bromide perbromide in dichloromethane/pyridine at -20 °C. The same reagent in dichloromethane at 0 °C produce the 2,6-bis(bromomethyl) 1,4-dihydropyridines.

متن کامل

First selective direct mono-arylation of piperidines using ruthenium-catalyzed C–H activation

ABSTRACT A Ru-catalyzed mono-arylation in α-position of saturated cyclic amines is reported employing a C-H activation protocol. Substitution of the pyridine directing group with a bulky group, e.g., trifluoromethyl in the 3-position, proved to be crucial to avoid bis-arylation. This highly selective transformation can be performed with different amines and arylboronate esters. Additionally, th...

متن کامل

Ruthenium(II)-catalysed remote C–H alkylations as a versatile platform to meta-decorated arenes

The full control of positional selectivity is of prime importance in C-H activation technology. Chelation assistance served as the stimulus for the development of a plethora of ortho-selective arene functionalizations. In sharp contrast, meta-selective C-H functionalizations continue to be scarce, with all ruthenium-catalysed transformations currently requiring difficult to remove or modify nit...

متن کامل

Cyanation and bromination of electron-rich aromatics by BrCN under solvent-free conditions catalyzed by AlCl3: A new examples of Beckmann-type rearrangement

A convenient route for cyanation and bromination of some electron-rich aromatics (anisole, 1,3-dimethoxybenzene, 1,4-dimethoxybenzene, 1,3,5-trimethoxybenzene and β-naphthol) by BrCN in the presence of aluminum trichloride (AlCl3), as catalyst, by grinding method under solvent-free conditions at room temperature to 60 °C was described in good yield. The structures of all obtained products were ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 54  شماره 

صفحات  -

تاریخ انتشار 2015