Stille Coupling of an Aziridinyl Stannatrane

An aziridinyl stannatrane <b>8</b> couples with aryl or alkenyl halides RX under modified Stille conditions to afford substituted aziridines. Efficient coupling at room temperature is possible in the best examples in the presence of (^<i>t</i>Bu₃P)₂Pd and CuOP­(O)­Ph₂ (CuDPP)

Enantioselective Synthesis of Cocaine C-1 Analogues using Sulfinimines (<i>N</i>-Sulfinyl Imines)

The first examples of cocaine analogues having substituents (methyl, ethyl, <i>n</i>-propyl, <i>n</i>-pentyl, and phenyl) at the C-1 position of the cocaine tropane skeleton were prepared by heating sulfinimine-derived α,β-unsaturated pyrrolidine nitrones. In the presence of the Lewis acid Al­(O<i>^t</i>Bu)₃ the nitrones undergo an intramolecular [3 + 2] cycloaddition to give tricyclic isoxazolidines that were transformed in three steps to the cocaine analogues. In the absence of the Lewis acid, lactams were formed resulting from rearrangement of the nitrone to an oxaziridine. A novel Pd- and base-promoted rearrangement of methanesulfonate salts of isoxazolidine to bridge bicyclic[4.2.1]­isoxazolidines was discovered

Enantioselective Synthesis of Cocaine C-1 Analogues using Sulfinimines (<i>N</i>-Sulfinyl Imines)

The first examples of cocaine analogues having substituents (methyl, ethyl, <i>n</i>-propyl, <i>n</i>-pentyl, and phenyl) at the C-1 position of the cocaine tropane skeleton were prepared by heating sulfinimine-derived α,β-unsaturated pyrrolidine nitrones. In the presence of the Lewis acid Al­(O<i>^t</i>Bu)₃ the nitrones undergo an intramolecular [3 + 2] cycloaddition to give tricyclic isoxazolidines that were transformed in three steps to the cocaine analogues. In the absence of the Lewis acid, lactams were formed resulting from rearrangement of the nitrone to an oxaziridine. A novel Pd- and base-promoted rearrangement of methanesulfonate salts of isoxazolidine to bridge bicyclic[4.2.1]­isoxazolidines was discovered

Enantioselective Synthesis of Cocaine C-1 Analogues using Sulfinimines (<i>N</i>-Sulfinyl Imines)

The first examples of cocaine analogues having substituents (methyl, ethyl, <i>n</i>-propyl, <i>n</i>-pentyl, and phenyl) at the C-1 position of the cocaine tropane skeleton were prepared by heating sulfinimine-derived α,β-unsaturated pyrrolidine nitrones. In the presence of the Lewis acid Al­(O<i>^t</i>Bu)₃ the nitrones undergo an intramolecular [3 + 2] cycloaddition to give tricyclic isoxazolidines that were transformed in three steps to the cocaine analogues. In the absence of the Lewis acid, lactams were formed resulting from rearrangement of the nitrone to an oxaziridine. A novel Pd- and base-promoted rearrangement of methanesulfonate salts of isoxazolidine to bridge bicyclic[4.2.1]­isoxazolidines was discovered

Enantioselective Synthesis of Cocaine C-1 Analogues using Sulfinimines (<i>N</i>-Sulfinyl Imines)

The first examples of cocaine analogues having substituents (methyl, ethyl, <i>n</i>-propyl, <i>n</i>-pentyl, and phenyl) at the C-1 position of the cocaine tropane skeleton were prepared by heating sulfinimine-derived α,β-unsaturated pyrrolidine nitrones. In the presence of the Lewis acid Al­(O<i>^t</i>Bu)₃ the nitrones undergo an intramolecular [3 + 2] cycloaddition to give tricyclic isoxazolidines that were transformed in three steps to the cocaine analogues. In the absence of the Lewis acid, lactams were formed resulting from rearrangement of the nitrone to an oxaziridine. A novel Pd- and base-promoted rearrangement of methanesulfonate salts of isoxazolidine to bridge bicyclic[4.2.1]­isoxazolidines was discovered

Enantioselective Synthesis of Cocaine C-1 Analogues using Sulfinimines (<i>N</i>-Sulfinyl Imines)

The first examples of cocaine analogues having substituents (methyl, ethyl, <i>n</i>-propyl, <i>n</i>-pentyl, and phenyl) at the C-1 position of the cocaine tropane skeleton were prepared by heating sulfinimine-derived α,β-unsaturated pyrrolidine nitrones. In the presence of the Lewis acid Al­(O<i>^t</i>Bu)₃ the nitrones undergo an intramolecular [3 + 2] cycloaddition to give tricyclic isoxazolidines that were transformed in three steps to the cocaine analogues. In the absence of the Lewis acid, lactams were formed resulting from rearrangement of the nitrone to an oxaziridine. A novel Pd- and base-promoted rearrangement of methanesulfonate salts of isoxazolidine to bridge bicyclic[4.2.1]­isoxazolidines was discovered

Enantioselective Synthesis of Cocaine C-1 Analogues using Sulfinimines (<i>N</i>-Sulfinyl Imines)

The first examples of cocaine analogues having substituents (methyl, ethyl, <i>n</i>-propyl, <i>n</i>-pentyl, and phenyl) at the C-1 position of the cocaine tropane skeleton were prepared by heating sulfinimine-derived α,β-unsaturated pyrrolidine nitrones. In the presence of the Lewis acid Al­(O<i>^t</i>Bu)₃ the nitrones undergo an intramolecular [3 + 2] cycloaddition to give tricyclic isoxazolidines that were transformed in three steps to the cocaine analogues. In the absence of the Lewis acid, lactams were formed resulting from rearrangement of the nitrone to an oxaziridine. A novel Pd- and base-promoted rearrangement of methanesulfonate salts of isoxazolidine to bridge bicyclic[4.2.1]­isoxazolidines was discovered