Novel Rhodamine Dyes via Suzuki Coupling of Xanthone Triflates with Arylboroxins

Abstract

Novel rhodamine dyes were prepared from xanthone precursors in a ‘one-pot’ procedure via reaction of the xanthone with trifluoromethanesulfonic anhydride followed by Pd-mediated Suzuki coupling between the xanthone triflate and an arylboroxin. Rhodamines with 9-(3- or 4-carboxyphenyl) and 9-(3-nitrophenyl) substituents were prepared by this procedure. The procedure also works well with thio- and selenoxanthones, but not with telluroxanthones.

Suzuki coupling - arylations - palladium - rhodamine dyes - arylboroxins

References and Notes

As laser dyes, fluorescent labels, and probes:

<A NAME="RS11209ST-1A">1a</A> Peterson OG. Tuccio SA. Snavely BB. Appl. Phys. Lett.  1970,  17:  245 

<A NAME="RS11209ST-1B">1b</A> Drexhage KH. Top. Appl. Phys.  1973,  1:  144 

<A NAME="RS11209ST-1C">1c</A> Karstens T. Kobs K. J. Phys. Chem.  1980,  84:  1871 

<A NAME="RS11209ST-1D">1d</A> Preininger C. Mohr GJ. Klimant I. Wolfbeis OS. Anal. Chim. Acta  1996,  334:  113 

<A NAME="RS11209ST-1E">1e</A> Liu J. Diwu Z. Leung W.-Y. Lu Y. Patch B. Hugland RP. Tetrahedron Lett.  2003,  44:  4355 

<A NAME="RS11209ST-1F">1f</A> Beija M. Afonso CAM. Martinho JMG. Chem. Soc. Rev.  2009,  38:  2410 

Biosensing with FRET:

<A NAME="RS11209ST-2A">2a</A> Adams SR. Harootounian AT. Buechler YJ. Taylos SS. Tsien RY. Nature (London)  1991,  349:  694 

<A NAME="RS11209ST-2B">2b</A> Martinez-Manez R. Sancenon F. Chem. Rev.  2003,  103:  4419 

<A NAME="RS11209ST-3">3</A> Electrochemiluminescence: Richter MM. Chem. Rev.  2004,  104:  3003 

Proton sensors:

<A NAME="RS11209ST-4A">4a</A> de Silva AP. Gunaratne HQN. Gunnlaugsson T. Huxley AJM. McCoy CP. Rademacher JT. Rice TE. Chem. Rev.  1997,  97:  1515 

<A NAME="RS11209ST-4B">4b</A> Vogel M. Rettig W. Sens D. Drexhage KH. Chem. Phys. Lett.  1988,  147:  452 

<A NAME="RS11209ST-5">5</A> Halide sensors: Anzenbacher P. Jursikova K. Sessler JL. J. Am. Chem. Soc.  2000,  122:  9350 

<A NAME="RS11209ST-6A">6a</A> Johnson LV. Walsh ML. Bockus BJ. Chen LB. J. Cell. Biol.  1981,  88:  526 

<A NAME="RS11209ST-6B">6b</A> Davis S. Weiss MJ. Wong JR. Lampidis TJ. Chen LB. J. Biol. Chem.  1985,  260:  13844 

<A NAME="RS11209ST-6C">6c</A> Bernal SD. Lampdis TJ. McIsaac RM. Chen LB. Science  1986,  222:  169 

<A NAME="RS11209ST-7A">7a</A> Tombline G. Donnelly DJ. Holt JJ. You Y. Ye M. Gannon MK. Nygren CL. Detty MR. Biochemistry  2006,  45:  8034 

<A NAME="RS11209ST-7B">7b</A> Tombline G. Holt JJ. Gannon MK. Donnelly DJ. Wetzel B. Sawada GA. Raub TJ. Detty MR. Biochemistry  2008,  47:  3294 

<A NAME="RS11209ST-7C">7c</A> Gannon MK. Holt JJ. Bennett SM. Wetzel BR. Loo TW. Bartlett MC. Clarke DM. Sawada GA. Higgins JW. Tombline G. Raub TJ. Detty MR. J. Med. Chem.  2009,  52:  3328 

<A NAME="RS11209ST-8A">8a</A> Brasseur N. Menard I. Forget A. El Jastimi R. Hamel R. Molfino NA. van Lier JE. Photochem. Photobiol.  2000,  72:  780 

<A NAME="RS11209ST-8B">8b</A> Pal P. Zeng H. Durocher G. Girard D. Li TC. Gupta AK. Giasson R. Blanchard L. Gaboury L. Balassy A. Turmel C. Laperriere A. Villeneuve L. Photochem. Photobiol.  1996,  53:  161 

<A NAME="RS11209ST-9A">9a</A> Shi J. Zhang X. Neckers DC. J. Org. Chem.  1992,  57:  4418 

<A NAME="RS11209ST-9B">9b</A> Parker CA. In Advances in Photochemistry   Vol. 2:  Noyes WA. Hammond GS. Pitts JN. Wiley Interscience; New York: 1964.  p.305 

<A NAME="RS11209ST-10A">10a</A> Ohulchanskyy T. Donnelly DJ. Detty MR. Prasad PN. J. Phys. Chem. B  2004,  108:  8668 

<A NAME="RS11209ST-10B">10b</A> Wagner SJ. Skripchenko A. Donnelly DJ. Ramaswamy K. Detty MR. Bioorg. Med. Chem.  2005,  13:  5927 

<A NAME="RS11209ST-10C">10c</A> Gibson SL. Holt JJ. Ye M. Donnelly DJ. Ohulchanskyy TY. You Y. Detty MR. Bioorg. Med. Chem.  2005,  13:  6394 

<A NAME="RS11209ST-10D">10d</A> Wagner SJ. Skripchenko A. Thompson-Montgomery D. Awatefe H. Donnelly DJ. Detty MR. Photochem. Photobiol.  2006,  76:  514 

<A NAME="RS11209ST-11">11</A> Detty MR. Gibson SL. Wagner S. J. Med. Chem.  2004,  47:  3897 

<A NAME="RS11209ST-12A">12a</A> Woodroofe CC. Lim MH. Bu W. Lippard SJ. Tetrahedron  2005,  61:  3097 

<A NAME="RS11209ST-12B">12b</A> Ioffe IS. Otten VF.
Zh. Obsh. Khim.  1962,  32:  1477 

<A NAME="RS11209ST-13A">13a</A> Bandichhor R. Petrescu AD. Vespa A. Kier AB. Schroeder F. Burgess K. Bioconjugate Chem.  2006,  17:  1219 

<A NAME="RS11209ST-13B">13b</A> Jiao G.-S. Castro JC. Thoresen LH. Burgess K. Org. Lett.  2005,  5:  3675 

<A NAME="RS11209ST-14A">14a</A> Gannon MK. Detty MR. J. Org. Chem.  2007,  72:  2647 

<A NAME="RS11209ST-14B">14b</A> Calitree BD. Donnelly DJ. Holt JJ. Gannon MK. Nygren C. Sukumaran DK. Autschbach J. Detty MR. Organometallics  2007,  26:  6248 

<A NAME="RS11209ST-15">15</A> Wu L. Burgess K. Org. Lett.  2009,  10:  1779 

<A NAME="RS11209ST-16">16</A> Miyaura N. Suzuki A. Chem. Rev.  1995,  95:  2457 

<A NAME="RS11209ST-17A">17a</A> Washburn RM. Levens El Albright CF. Billig FA. Org. Synth., Coll. Vol. 4  1963,  68 

<A NAME="RS11209ST-17B">17b</A> Wu X. Liu X. Zhao G. Tetrahedron: Asymmetry  2005,  16:  2299 

<A NAME="RS11209ST-18">18</A> Tsukamoto H. Uchiyama T. Suzuki T. Kondo Y. Org. Biomol. Chem.  2008,  6:  3005 

<A NAME="RS11209ST-19">19</A> Cioffi CL. Spencer WT. Justin J. Richards JJ. Herr RJ. J. Org. Chem.  2004,  69:  2210 

<A NAME="RS11209ST-20">20</A>

Trifluoromethanesulfonic anhydride (61.7 µL, 0.367 mmol, 1.1 equiv) was added to 3,6-dimethylaminoxanth-9-one 1-E (1.0 equiv 0.334 mmol) in MeCN (15 mL). The resulting solution was stirred for 20 min at ambient temperature. PdCl₂(PPh₃)₂ (23 mg, 0.033 mmol, 0.1 equiv), Na₂CO₃ (106 mg, 1.00 mmol, 3.0 equiv), and arylboroxin 4 (0.334 mmol, 1.0 equiv) were added, and the temperature was increased to 55 ˚C. The reaction was monitored by visible spectroscopy for the appearance of the dye chromophore and disappear-ance of the chromophore of triflate 2-E (20 min for 7-S to
4.5 h for 8-S). The reaction mixture was cooled to ambient temperature, and H₂O (15 mL) was added. The dye was extracted with CH₂Cl₂ (5 × 20 mL), and the combined extracts were concentrated onto SiO₂ and dry loaded onto
a column of SiO₂. A gradient elution system (10% Et₂O-CH₂Cl₂, 40% Et₂O-CH₂Cl₂, 5% MeOH-CH₂Cl₂, and 10% MeOH-CH₂Cl₂) separated recovered starting material from rhodamine/rosamine dye isolated as a mixture of triflate and boronate salts. The dye was dissolved in AcOH (3 mL), and 30% HPF₆ or concentrated HCl was added dropwise until the characteristic color of the rhodamine/rosamine faded. The reaction mixture was poured into stirring ice H₂O, and the dye was collected by filtration. The ion exchange was repeated for a total of 3 times. The success of the ion exchange was confirmed by elemental analysis (±0.4% in C, H, N).

<A NAME="RS11209ST-21">21</A>

Analytical Data for 8-O
Mp >260 ˚C. ^¹H NMR (500 MHz, CD₂Cl₂): δ = 8.35 (d, 2 H, J = 8.0 Hz), 7.47 (d, 2 H, J = 8.0 Hz), 7.41 (d, 2 H, J = 9.5 Hz), 6.96 (dd, 2 H, J = 2.0, 9.5 Hz), 6.82 (d, 2 H, J = 2.0 Hz), 3.31 (s, 12 H). ^¹³C NMR (75.5 MHz, CD₃OD): δ = 168.7, 159.2, 159.0, 158.1, 137.9, 133.8, 132.5, 131.1, 131.0, 115.8, 114.3, 97.7, 41.0. UV/vis: λ_max (CH₂Cl₂) = 568 nm (ε 1.10˙10⁵ M^-¹ cm^-¹). ESI-HRMS: m/z calcd for C₂₄H₂₃N₂O₃ ⁺: 387.1703; found: 387.1720.
Analytical Data for 8-S
Mp >260 ˚C. ^¹H NMR (500 MHz, CD₃OD): δ = 8.17 (d, 2 H, J = 7.0 Hz), 7.36 (d, 2 H, J = 7.0 Hz), 7.28 (d, 2 H, J = 9.5 Hz), 7.24 (d, 2 H, J = 2.5 Hz), 7.01 (dd, 2 H, J = 2.5, 9.5 Hz), 3.19 (s, 12 H). ^¹³C NMR (75.5 MHz, CD₃OD): δ = 160.3, 154.2, 144.9, 139.3, 136.9, 130.5 (br, 2 C), 129.7, 119.4, 115.9, 106.0, 40.8. UV/vis: λ_max (MeOH) = 582 nm (ε 7.91˙10⁴ M^-¹ cm^-¹). ESI-HRMS: m/z calcd for C₂₄H₂₃N₂O₂S⁺: 403.1475; found: 403.1468.
Analytical Data for 9-O
Mp >260 ˚C. ^¹H NMR (500 MHz, CD₃OD): δ = 8.24 (d, 1 H, J = 8.0 Hz), 8.00 (s, 1 H), 7.72 (t, 1 H, J = 7.5 Hz), 7.62 (d, 1 H, J = 7.5 Hz), 7.26 (d, 2 H, J = 9.0 Hz), 7.03 (dd, 2 H, J = 2.0, 9.0 Hz), 6.91 (d, 2 H, J = 2.0 Hz), 3.23 (s, 12 H). ^¹³C NMR (75.5 MHz, CD₂Cl₂/CD₃OD): δ = 168.4, 159.0, 158.6, 158.0, 134.5, 133.4, 132.3, 132.2, 131.4, 131.2, 130.1, 115.4, 114.4, 97.5, 41.0. UV/vis: λ_max (MeOH) = 562 nm (ε 1.03˙10⁶ M^-¹ cm^-¹). ESI-HRMS: m/z calcd for C₂₄H₂₃N₂O₃ ⁺: 387.1703; found: 387.1704.
Analytical Data for 9-S
^¹H NMR (500 MHz, CD₃CO₂D/CD₂Cl₂): δ = 8.31 (d, 1 H, J = 7.5 Hz), 8.02 (s, 1 H), 7.74 (t, 1 H, J = 7.5 Hz), 7.60 (d, 1 H, J = 7.5 Hz), 7.32 (d, 2 H, J = 9.5 Hz), 7.20 (d, 2 H, J = 2.0 Hz), 6.95 (dd, 2 H, J = 2.0, 9.5 Hz), 3.25 (s, 12 H). ^¹³C NMR (75.5 MHz, CD₃OD): δ = 160.6, 154.7, 145.4, 137.2, 136.5, 132.9, 131.4, 131.2, 129.5, 119.9, 116.3, 106.5, 40.8. UV/vis: λ_max (MeOH) = 579 nm (ε 7.26˙10⁴
M^-¹ cm^-¹). ESI-HRMS: m/z calcd for C₂₄H₂₃N₂O₂S⁺: 403.1475; found: 403.1467.
Analytical Data for 10-O
^¹H NMR (500 MHz, CD₂Cl₂): δ = 8.53 (dd, 1 H, J = 2.0, 8.0 Hz), 8.28 (t, 1 H, J = 2.0 Hz), 7.91 (t, 1 H, J = 8.0 Hz), 7.81 (d, 1 H, J = 8.0 Hz), 7.27 (d, 2 H, J = 9.0 Hz), 6.98 (dd, 2 H, J = 2.0, 9.0 Hz), 6.88 (d, 2 H, J = 2.0 Hz), 3.32 (s, 12 H). ^¹³C NMR (75.5 MHz, CD₂Cl₂): δ = 158.1, 157.8, 154.8, 148.7, 135.9, 131.4, 131.0, 125.4, 124.6, 115.1, 113.7, 97.2, 41.3. UV/vis: λ_max (CH₂Cl₂) = 574 nm (ε 6.77˙10⁴ M^-¹ cm^-¹). ESI-HRMS: m/z calcd for C₂₃H₂₂N₃O₃ ⁺: 388.1656; found: 388.1660.
Analytical Data for 10-S
Mp >260 ˚C. ^¹H NMR (500 MHz, CD₂Cl₂): δ = 8.50 (dt, 1 H, J = 1.0, 8.0 Hz), 8.20 (s, 1 H), 7.90 (t, 1 H, J = 8.0 Hz), 7.73 (d, 1 H, J = 8.0 Hz), 7.28 (d, 2 H, J = 9.0 Hz), 7.17 (d, 2 H, J = 2.0 Hz), 6.97 (dd, 2 H, J = 2.0, 9.0 Hz), 3.29 (s, 12 H). ^¹³C NMR (75.5 MHz, CD₂Cl₂): δ = 156.5, 153.9, 148.6, 144.7, 137.5, 136.0, 135.8, 130.8, 124.7, 124.4, 119.0, 116.1, 106.2, 41.0. UV/vis: λ_max (CH₂Cl₂) = 593 nm
(ε 1.02˙10⁵ M^-¹ cm^-¹). ESI-HRMS: m/z calcd for C₂₃H₂₂N₃O₂S⁺: 404.1427; found: 404.1420.