High Affinity Carboxylate Binding Using Neutral Urea-Based Receptors with Internal Lewis Acid Coordination

Hughes, Martin Patrick; Shang, Maoyu; Smith, Bradley D.

doi:10.1021/jo9608026

Cited by 48 publications

(18 citation statements)

References 17 publications

(17 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Smith incorporated Lewis acid coordination to polarise the urea moiety. 74 Binding studies were carried out with a range of receptors 103-106 in DMSO-d 6 using TBA acetate as guest. Receptors 103 and 104 gave similar binding constants (K a = 390 M Ϫ1 and K a = 370 M Ϫ1 respectively) due to the similarity in electronegativities of hydrogen and boron, and in each case 1 : 1 binding was verified by Job plot analysis.…”

Section: Ureas and Thioureasmentioning

confidence: 99%

Synthetic receptors for carboxylic acids and carboxylates

Fitzmaurice

Kyne

Douheret

et al. 2002

J. Chem. Soc., Perkin Trans. 1

260

147

View full text Add to dashboard Cite

Section: Ureas and Thioureasmentioning

confidence: 99%

Synthetic receptors for carboxylic acids and carboxylates

Fitzmaurice

Kyne

Douheret

et al. 2002

J. Chem. Soc., Perkin Trans. 1

260

147

View full text Add to dashboard Cite

“…[4] A variety of receptors containing one or more urea subunits have been designed and tested for anion recognition and sensing over the past years. [5][6][7][8][9][10][11][12] A major element of selectivity is given by the energy of the receptor-anion interaction: in fact, the strongest hydrogen-bond interactions are established with anions that contain the most electronegative atoms, for example, F (fluoride) and O (carboxylates, inorganic oxoanions), and that display the most pronounced basic tendencies in the chosen solvent. On the other hand, in most cases electron-withdrawing substituents have been appended to the urea framework in order to polarise the NÀ H bonds and to increase its hydrogen-bond donor tendencies.…”

Section: Introductionmentioning

confidence: 99%

Anion‐Induced Urea Deprotonation

Boiocchi¹,

Boca

Esteban‐Gómez

et al. 2005

Chemistry A European J

255

119

View full text Add to dashboard Cite

The urea-based receptor 1 (1-(7-nitrobenzo[1,2,5]oxadiazol-4-yl)-3-(4-nitrophenyl)urea, L--H), interacts with X- ions in MeCN, according to two consecutive steps: 1) formation of a hydrogen-bond complex [L--H...X]-; 2) deprotonation of L--H to give L- and [HX2]-, as shown by spectrophotometric and 1H NMR titration experiments. Step 2) takes place with more basic anions (fluoride, carboxylates, dihydrogenphosphate), while less basic anions (Cl-, NO2-, NO3-) do not induce proton transfer. On crystallisation from a solution containing L--H and excess Bu4NF, the tetrabutylammonium salt of the deprotonated urea derivative (Bu4N[L]) was isolated and its crystal and molecular structure determined.

show abstract

“…2). 20,21 The results of early studies initiated in our laboratory to probe tuning of the urea catalyst activity through internal Lewis acid incorporation are presented herein.…”

mentioning

confidence: 99%