catalytic enantio- and diastereoselective nitro-Mannichreaction of α-amido sulfones in the mixed solvent of toluene/H2O has been realized using a phase-transfer catalyst (PTC) derived from cinchona alkaloids and N-benzotriazole. It performed well over a wide range of substrates to give the desired products in good yields (up to 94%) with excellent enantioselectivities (up to 99% ee) and diastereoselectivities
使用衍生自金鸡纳生物碱和N-苯并三唑的相转移催化剂(PTC)实现了α-酰胺基砜在甲苯/ H 2 O混合溶剂中的催化对映体和非对映体的硝基曼尼希反应。它在各种底物上均表现良好,以高收率(最高94%)提供所需的产品,并具有出色的对映选择性(最高99%ee)和非对映选择性(最高99:1)。
Synthesis of β-Allenylamines by Addition of Chloroprene Grignards to <i>N</i>-Boc Imines
作者:Arne G. A. Geissler、Bernhard Breit
DOI:10.1021/acs.orglett.2c03105
日期:2022.11.4
The γ-selective addition of chloroprene Grignards to aromatic N-Boc aldimines enabled by 2,2′-dimorpholinodiethyl ether (DMDEE) yields the corresponding N-Boc protected β-allenylamines in good yields and regioselectivities. Transmetalation to zinc bromide also allows the addition of chloroprene Grignard to aliphatic aldimines in good yields. The obtained β-allenylamines were shown to be easily deprotected
Synthesis of α,α-Difluoro-β-amino Ketones from N-Boc-α-Amidosulfones and Pentafluoro-gem-diols
作者:Baharul Islam、Suresh P. Sulochana、David A. Colby
DOI:10.1021/acs.joc.3c02181
日期:2024.5.3
circumvent the synthesis and isolation of imines, a method was devised to construct α,α-difluoro-β-amino ketones from N-Boc-α-amidosulfones. The reactive nucleophiles, difluoroenolates, are generated in situ from the pentafluoro-gem-diols using cesium fluoride in pyridine. NMR studies confirm the role of the α-amidosulfones in this process. Incubation of the α,α-difluoro-β-amino ketones in rat serum