Condensation of Arylboroxine Structures on Lewis Basic Copolymers as a Noncovalent Strategy toward Polymer Functionalization

Iovine, Peter M.; Fletcher, Matthew N; Lin, Shirley

doi:10.1021/ma0613741

Cited by 33 publications

(22 citation statements)

References 37 publications

(58 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 H NMR is the most reliable method for distinguishing boronic acid, boronate ester, and boroxine since the aromatic protons ortho to the boron atom show distinct chemical shifts for all three states 11,20–22 . 1 H NMR analysis ( d 6 ‐acetone/D 2 O) for all boronic acid‐containing polymers show characteristic resonances at 7.9 ppm and are devoid of boronate ester resonances at 7.8 and 1.3 ppm (see Supporting Information).…”

Section: Resultsmentioning

confidence: 99%

Synthesis, characterization, and star polymer assembly of boronic acid end‐functionalized polycaprolactone

Korich

Walker

Hincke

et al. 2010

J. Polym. Sci. A Polym. Chem.

Self Cite

View full text Add to dashboard Cite

Boronic acid end-functionalized polycaprolactone (PCL) polymers were synthesized by ring-opening polymerization using a pinacol boronate ester-containing (Bpin) initiator. The polymerization provides access to boron-terminated polymers (i.e. Bpin-PCL-OH) with narrow molecular weight distributions (PDI ¼ 1.09). Postsynthetic manipulation of the polymer's terminal hydroxyl group by copper-catalyzed azide-alkyne cycloaddition chemistry provides a series of bis end-functionalized polymers with significant structural diversity at the termini. Deprotection of the boronate ester end group was accomplished with an acidic solid phase DOWEX resin. The boronate ester deprotection methodology does not result in hydrolysis of the polymeric backbone. The boronic acid-tipped polymers were converted into star polymer assemblies using thermal dehydration and ligand-facilitated trimerization. Thermal dehydration of (HO) 2 B-PCL-OAc to the corresponding boroxine-based star polymer assembly was inefficient and lead to degradation products. Ligand-facilitated trimerization using either pyridine or 7-azaindole as the Lewis base was efficient and mild. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 5767-5774, 2010

show abstract

Section: Resultsmentioning

confidence: 99%

Synthesis, characterization, and star polymer assembly of boronic acid end‐functionalized polycaprolactone

Korich

Walker

Hincke

et al. 2010

J. Polym. Sci. A Polym. Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

“…First, binding Lewis basic species such as the N,N-dimethylaminomethyl group of 3a to arylboroxine rings decreases arylboroxine Lewis acidity and generally results in upfield 19 F NMR shifts relative to the corresponding unligated arylboroxine. 22 Therefore, the chemical shift of the −110 ppm 19 F resonance, assigned as 3a, is justified based on the relative position of the resonances of 4a and 2a. In addition, the chemical shift of the resonance assigned as 3a in Fig.…”

mentioning

confidence: 99%

Hetero-arylboroxines: the first rational synthesis, X-ray crystallographic and computational analysis

et al. 2008

Self Cite

View full text Add to dashboard Cite

show abstract

“…As shown in Figure 3 a,b, the peaks for the 2′ and 3′ hydroxyl groups disappeared, and the 2′ and 3′ proton signals were shifted considerably upfield upon the addition of 11c . In Figure 3 c–e, it was assumed that the peaks at 21 ppm, 28 ppm and 32 ppm correspond to a 2,4,6-tris[4-(trifluorometyl)phenyl]boroxine pyridine complex, the proposed structure of which is 49 (some NMR spectra of boroxine pyridine complexes were reported [ 69 , 70 , 71 ]), 11c or 2,4,6-tris[4-(trifluorometyl)phenyl]boroxine and the desired boronic ester 47 , respectively. In Figure 3 f–h, we assumed that the peaks at −63.3 ppm, −63.2 ppm and −62.8 ppm correspond to 47 , 11c or 2,4,6-tris[4-(trifluorometyl)phenyl]boroxine and 49 , respectively.…”

Section: Resultsmentioning

confidence: 99%

Synthesis of Disaccharide Nucleosides Utilizing the Temporary Protection of the 2′,3′-cis-Diol of Ribonucleosides by a Boronic Ester

2017

View full text Add to dashboard Cite

Disaccharide nucleosides are an important class of natural compounds that have a variety of biological activities. In this study, we report on the synthesis of disaccharide nucleosides utilizing the temporary protection of the 2′,3′-cis-diol of ribonucleosides, such as adenosine, guanosine, uridine, 5-metyluridine, 5-fluorouridine and cytidine, by a boronic ester. The temporary protection of the above ribonucleosides permits the regioselective O-glycosylation of the 5’-hydroxyl group with thioglycosides using a p-toluenesulfenyl chloride (p-TolSCl)/silver triflate (AgOTf) promoter system to afford the corresponding disaccharide nucleosides in fairly good chemical yields. The formation of a boronic ester prepared from uridine and 4-(trifluoromethyl)phenylboronic acid was examined by 1H, 11B and 19F NMR spectroscopy.

show abstract

Condensation of Arylboroxine Structures on Lewis Basic Copolymers as a Noncovalent Strategy toward Polymer Functionalization

Cited by 33 publications

References 37 publications

Synthesis, characterization, and star polymer assembly of boronic acid end‐functionalized polycaprolactone

Synthesis, characterization, and star polymer assembly of boronic acid end‐functionalized polycaprolactone

Hetero-arylboroxines: the first rational synthesis, X-ray crystallographic and computational analysis

Synthesis of Disaccharide Nucleosides Utilizing the Temporary Protection of the 2′,3′-cis-Diol of Ribonucleosides by a Boronic Ester

Contact Info

Product

Resources

About