报道了β-、γ-和δ-不饱和N-酰基磺酰胺环异构化为N-磺酰基内酰胺和亚胺酸酯。这种转变是在 Co III (salen) 催化剂的存在下使用t -BuOOH 或空气作为氧化剂进行的。该方法显示出良好的官能团耐受性(烷基、芳基、杂芳基、醚、N -Boc),并提供了一类尚未开发的环状结构单元。研究了转化的强溶剂依赖性,并强调了N-磺酰亚胺酯产品类的合成多功能性。
A Palladium-Catalyzed Aminoalkynylation Strategy towards Bicyclic Heterocycles: Synthesis of (±)-Trachelanthamidine
作者:Stefano Nicolai、Cyril Piemontesi、Jérôme Waser
DOI:10.1002/anie.201100718
日期:2011.5.9
Sweet cyclizations: The synthesis of pyrrolizidines and indolizidines has been achieved. Olefins were subjected to an intramolecular palladium‐catalyzed aminoalkynylation with the hypervalent iodine reagent TIPS‐EBX. After removal of the protecting group, a two‐step cyclization sequence and subsequent reduction led to the natural product (±)‐trachelanthamidine (see scheme; TIPS‐EBX=triisopropylsilyl
Dormant versus Evolving Aminopalladated Intermediates: Toward a Unified Mechanistic Scenario in Pd<sup>II</sup>-Catalyzed Aminations
作者:Jamshid Rajabi、Mélanie M. Lorion、Vu Linh Ly、Frédéric Liron、Julie Oble、Guillaume Prestat、Giovanni Poli
DOI:10.1002/chem.201302744
日期:2014.2.3
PdII‐catalyzed alkene aminopalladation and allylic CH activation are two competing reaction sequences sharing the same reaction conditions. This study aimed at understanding the factors that bias one or the other path in the intramolecular oxidative cyclization of two types of N‐tosyl amidoalkenes. The results obtained are in accord with the initial generation of a high‐energy cyclic (5‐ or 6‐membered)
Striking AcOH Acceleration in Direct Intramolecular Allylic Amination Reactions
作者:Fady Nahra、Frédéric Liron、Guillaume Prestat、Carlo Mealli、Abdelatif Messaoudi、Giovanni Poli
DOI:10.1002/chem.200901946
日期:2009.10.26
An acid–base reaction to speed up a sluggish catalytic cycle! AcOH as the solvent enables extraordinarily fast and efficient PdII‐catalysed, directintramolecularallylicaminations, assisting the benzoquinone‐mediated palladium reoxidation and ionisation of the intermediate palladium complexes (see scheme). The structural and energetic aspects of such a key step of the catalytic cycle are illustrated
Iodoamination of Alkenyl Sulfonamides by Potassium Iodide and Hydrogen Peroxide in Aqueous Medium
作者:Sabrina Giofrè、Roberto Sala、Egle Maria Beccalli、Leonardo Lo Presti、Gianluigi Broggini
DOI:10.1002/hlca.201900088
日期:2019.7
A procedure for the iodoamination of unfunctionalized olefins tethered to a tosyl‐protected NH‐group has been developed. The combined use of KI and H2O2 in aqueous medium was effective for the preparation of iodomethyl‐substituted nitrogen‐containing heterocycles. The selective exo‐trig iodocyclization provided 1,2‐bifunctional 5‐, 6‐, and 7‐membered cyclic skeletons.
已经开发了一种方法,用于将未官能化的烯烃束缚在甲苯磺酰基保护的NH-基团上进行碘化。在水性介质中联合使用KI和H 2 O 2可以有效地制备碘甲基取代的含氮杂环。选择性的exo-trig碘环化提供了1,2-双功能的5、6和7元环状骨架。