N-acylsulfonamide linker activation by Pd-catalyzed allylation.

نویسندگان

  • Yi He
  • Jesse P Wilkins
  • Laura L Kiessling
چکیده

N-Acylsulfonamide safety-catch linkers are versatile tools in solid-phase organic synthesis because of their stability. This stability necessitates linker activation prior to compound cleavage. Here, we demonstrate that the N-acylsulfonamide group can react with a pi-allyl palladium complex and that these mild and neutral conditions can be exploited for linker activation. The advantages of this process are illustrated by its use in the efficient synthesis of thioesters. We anticipate that this activation method will extend the utility of the N-acylsulfonamide group. [reaction: see text]

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

Additive-Free Pd-Catalyzed α-Allylation of Imine-Containing Heterocycles

An additive-free Pd-catalyzed α-allylation of different imino-group-ontaining heterocycles is reported. The activation of α-CH pronucleophiles (pKa (DMSO) > 25) occurs without the addition of strong bases or Lewis acids using only the Pd/Xantphos catalyst system. The reaction scope has been studied for various 5- and 6-membered nitrogen-containing heterocycles (yields up to 96%). Mechanistic in...

متن کامل

Palladium-catalyzed mono-N-allylation of unprotected amino acids with 1,1-dimethylallyl alcohol in water.

Palladium-catalyzed N-allylation of unprotected amino acids with 1,1-dimethylallyl alcohol were carried out. The reaction in the presence of Pd(OAc)(2) (5 mol%), sodium diphenylphosphinobenzene-3-sulfonate (TPPMS, 10 mol%), and AcONa (2 equiv) in water at 120 °C for 16 h in a sealed tube gave only mono-N-allylated amino acids in good yield.

متن کامل

Regiospecific decarboxylative allylation of nitriles.

Palladium-catalyzed decarboxylative alpha-allylation of nitriles readily occurs with use of Pd(2)(dba)(3) and rac-BINAP. This catalyst mixture also allows the highly regiospecific alpha-allylation of nitriles in the presence of much more acidic alpha-protons. Thus, the reported method provides access to compounds that are not readily available via base-mediated allylation chemistries. Lastly, m...

متن کامل

[Development of unprotected syntheses in aqueous media].

Introduction of carbon side chain at C(3)-position of indole ring was accomplished by using Pd-catalyzed allylation and vinylation. The selective vinylation at C(3)-position of 4-bromoindole was applied to the synthesis of optically active 4-bromotryptophan derivatives, which was used as a starting material for the synthesis of several optically active ergot alkaloids, which were clavicipitic a...

متن کامل

Unexpected effect of the fluorine atom on the optimal ligand-to-palladium ratio in the enantioselective Pd-catalyzed allylation reaction of fluorinated enol carbonates.

The enantioselective Pd-catalyzed allylation reaction of fluorinated allyl enol carbonates is presented; a key feature of this transformation is the important effect of the ligand-to-palladium ratio on the enantioselectivity of the alpha-fluoroketones, since using a ligand excess (L/Pd ratio = 1.25 : 1) led to moderate results (30-76% ee), while using a L/Pd ratio <1 : 1.67 (to as low as 1 : 4)...

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:
  • Organic letters

دوره 8 12  شماره 

صفحات  -

تاریخ انتشار 2006