89840-81-3Relevant academic research and scientific papers
Stereoinversion of Unactivated Alcohols by Tethered Sulfonamides
Marcyk, Paul T.,Jefferies, Latisha R.,AbuSalim, Deyaa I.,Pink, Maren,Baik, Mu-Hyun,Cook, Silas P.
supporting information, p. 1727 - 1731 (2019/01/21)
The direct, catalytic substitution of unactivated alcohols remains an undeveloped area of organic synthesis. Moreover, catalytic activation of this difficult electrophile with predictable stereo-outcomes presents an even more formidable challenge. Described herein is a simple iron-based catalyst system which provides the mild, direct conversion of secondary and tertiary alcohols to sulfonamides. Starting from enantioenriched alcohols, the intramolecular variant proceeds with stereoinversion to produce enantioenriched 2- and 2,2-subsituted pyrrolidines and indolines, without prior derivatization of the alcohol or solvolytic conditions.
A Hydrazone-Based exo-Directing-Group Strategy for β C-H Oxidation of Aliphatic Amines
Huang, Zhongxing,Wang, Chengpeng,Dong, Guangbin
supporting information, p. 5299 - 5303 (2016/04/26)
Described is a new hydrazone-based exo-directing group (DG) strategy developed for the functionalization of unactivated primary β C-H bonds of aliphatic amines. Conveniently synthesized from protected primary amines, the hydrazone DGs are shown to site-selectively promote the β-acetoxylation and tosyloxylation via five-membered exo-palladacycles. Amines with a wide scope of skeletons and functional groups are tolerated. Moreover, the hydrazone DG can be readily removed, and a one-pot C-H acetoxylation/DG removal protocol was also discovered. All about the DGs: A hydrazone-based exo-directing group (DG) strategy is developed for the functionalization of unactivated primary β C-H bonds of aliphatic amines. The hydrazone DGs can be conveniently installed and removed, and promote β-acetoxylation and tosyloxylation via a five-membered exo-palladacycle. PG=protecting group, Ts=4-toluenesulfonyl.
An efficient method for the preparation of monoalkylated sulfonamides from unsubstituted sulfonamides and alkyl diphenylphosphinites by oxidation-reduction condensation using trimethylsilylmethyl azide
Aoki, Hidenori,Kuroda, Kiichi,Mukaiyama, Teruaki
, p. 1266 - 1267 (2007/10/03)
An efficient method for monoalkylation of unsubstituted sulfonamides was established by using alkyl diphenylphosphinites, sulfonamides and trimethylsilylmethyl azide and the monoalkylated sulfonamides were afforded in good yields under neutral conditions.
ULTRAMINE: A high-capacity polyethylene-imine-based polymer and its application as a scavenger resin
Roice, Michael,Christensen, Soren F.,Meldal, Morten
, p. 4407 - 4415 (2007/10/03)
The synthesis of a novel high-loading polyethylene-imine resin (ULTRAMINE) is described, and its application as a scavenger resin in various acylation reactions is demonstrated. The inverse suspension polymerization technique was used for the synthesis of well-defined spherical polymer beads. Polymer beads with different cross-linking densities were synthesized according to the degree of acryloylation of the polyethylene-imine polymer. The resin was characterized by various spectroscopic techniques. The size, shape, and morphological features of the resin were demonstrated by microscopy. The resin showed excellent swelling properties in both polar and nonpolar solvents. The chemical stability of the resin in various reagents and solvents was investigated and monitored by IR spectroscopy. The mechanical stability of the beads was determined by a single-bead compressive experiment. The ULTRAMINE beads can be used as an excellent scavenger for excess acylating reagent, as demonstrated for a variety of reactions. UL-TRAMINE-red resin was derived from ULTRAMINE through exhaustive reduction of the amide carbonyl groups to yield an all-amine resin.
