3-Amino-5-bromo-2-iodo­pyridine

The reaction of 3-amino-5-bromo­pyridine with N-iodo­succinimide in the presence of acetic acid produces the title compound, C5H4BrIN, with an iodo substituent in position 2 of the pyridine ring. The crystal structure features rather weak inter­molecular N—H⋯N hydrogen bonds linking the mol­ecules into chains along the z axis of the crystal

Copper-catalyzed synthesis of masked (hetero)aryl sulfinates

Catalysis using substoichiometric copper facilitates the synthesis of masked (hetero)aryl sulfinates under mild, base-free conditions from aryl iodides and the commercial sulfonylation reagent sodium 1-methyl 3-sulfinopropanoate (SMOPS). The development of a tert-butyl ester variant of the SMOPS reagent allowed the use of aryl bromide substrates. The sulfones thus generated can be unmasked and functionalized in situ to form a variety of sulfonyl-containing functional groups

Diastereoselective access to substituted 4-aminopiperidines via a pyridine reduction approach

We describe herein a diastereoselective approach to access substituted-4-aminopiperidines from pyridine precursors. This methodology has successfully been applied to synthesize 2-alkyl substrates as well as more complex molecular entities of interest to the pharmaceutical industry

A Parallel Approach to 7‑(Hetero)arylpyrazolo[1,5‑<i>a</i>]pyrimidin-5-ones

A modular, two-pot assembly of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones from aryl/heteroaryl halides and aminopyrazoles in library format was developed. Sonogashira coupling of aryl bromides with triethyl orthopropiolate, followed by in situ orthoester hydrolysis, provides access to β-aryl ynoates, which undergo regioselective cyclocondensation with aminopyrazoles. The ability to vary the C7 vector of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones in two steps using readily available (hetero)­aryl halides significantly enhances synthetic access to this challenging vector

A Parallel Approach to 7‑(Hetero)arylpyrazolo[1,5‑<i>a</i>]pyrimidin-5-ones

A modular, two-pot assembly of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones from aryl/heteroaryl halides and aminopyrazoles in library format was developed. Sonogashira coupling of aryl bromides with triethyl orthopropiolate, followed by in situ orthoester hydrolysis, provides access to β-aryl ynoates, which undergo regioselective cyclocondensation with aminopyrazoles. The ability to vary the C7 vector of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones in two steps using readily available (hetero)­aryl halides significantly enhances synthetic access to this challenging vector

A Parallel Approach to 7‑(Hetero)arylpyrazolo[1,5‑<i>a</i>]pyrimidin-5-ones

A modular, two-pot assembly of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones from aryl/heteroaryl halides and aminopyrazoles in library format was developed. Sonogashira coupling of aryl bromides with triethyl orthopropiolate, followed by in situ orthoester hydrolysis, provides access to β-aryl ynoates, which undergo regioselective cyclocondensation with aminopyrazoles. The ability to vary the C7 vector of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones in two steps using readily available (hetero)­aryl halides significantly enhances synthetic access to this challenging vector

A Parallel Approach to 7‑(Hetero)arylpyrazolo[1,5‑<i>a</i>]pyrimidin-5-ones

A modular, two-pot assembly of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones from aryl/heteroaryl halides and aminopyrazoles in library format was developed. Sonogashira coupling of aryl bromides with triethyl orthopropiolate, followed by in situ orthoester hydrolysis, provides access to β-aryl ynoates, which undergo regioselective cyclocondensation with aminopyrazoles. The ability to vary the C7 vector of 7-arylpyrazolo­[1,5-<i>a</i>]­pyrimidones in two steps using readily available (hetero)­aryl halides significantly enhances synthetic access to this challenging vector

Diastereoselective access to substituted 4-aminopiperidines via a pyridine reduction approach

We describe herein a diastereoselective approach to access substituted-4-aminopiperidines from pyridine precursors. This methodology has successfully been applied to synthesize 2-alkyl substrates as well as more complex molecular entities of interest to the pharmaceutical industry