High-Load, Oligomeric Dichlorotriazine: A Versatile ROMP-Derived Reagent and Scavenger

Abstract

A new high-load, soluble oligomeric dichlorotriazine (ODCT) reagent derived from ring-opening metathesis polymerization (ROMP) is reported as an effective coupling reagent, scavenger of nucleophilic species and activator of DMSO for the classic Swern oxidations. Two variants of this reagent 2GODCT 4 and 1GODCT 16, possessing theoretical loads of 5.3 mmol/g and 7.3 mmol/g, respectively, have been synthesized. Preparation was accomplished via simple synthetic protocols affording free flowing powders, amenable for large-scale production. Removal of the spent oligomeric reagent was achieved via either precipitation of the spent reagent or simple filtration utilizing a silica SPE, followed by solvent removal, to deliver products in excellent yield and purity. In addition, the corresponding norbornenyl monomer 3 was successfully demonstrated in a couple-ROMP-filter protocol utilizing in-situ polymerization, achieving comparable results versus the corresponding oligomeric variant.

SNAr-Based, Facile Synthesis of a Library of Benzothiaoxazepine-1,1′-dioxides

“…Utilizing previously published conditions as a starting point, 19 scavenging of the crude reaction mixture utilizing 3 equivalents of 2G ODCT 50 at 110 °C (thermal heating), yielded the desired crude product in >90% purity by 1 H NMR [Table 3, entry 1-3]. Despite these results, having to scavenge crude reactions for 10 h in a parallel format was not an optimal protocol for library production.…”

Synthesis of a new fluorescent macrocyclic α-amino acid derivative via tandem cross-enyne/ring-closing metathesis cascade catalyzed by ruthenium based catalysts

“…Several methods are available to assemble macrocyclics [4e12], however, there are no reports for the synthesis of macrocyclic AAA by tandem metathesis sequence. In this regard, we conceived a simple, diversity oriented, fragment coupling approach for the synthesis of macrocyclic AAA derivatives based on tandem cross-enyne/ring-closing metathesis (CEeRCM) as a key step [13,14].…”

Catalytic role of PPh3 and its polymer bound analog in the amidation of carboxylic acids mediated by 2,4,6-trichloro-1,3,5-triazine

“…Systems such as TCT/Et 3 N 7,12 or N-methylmorpholine (NMM), 5,6,9 oligomeric dichlorotriazine/NMM, 13 CDMT/NMM, [14][15][16]10,17,18 CDMT/N,N-dimethylglycine esters, 19,20 and CDMT/chiral tertiary amines 21 have all been successfully applied to the amidation of various carboxylic acids. While the mechanism for the TCT-mediated reactions remains unclear, 1 the added tertiary amine is believed to play an important role (apart from acting as a base) in functioning as a catalyst for preactivation of the triazine ring toward nucleophilic substitution.…”