Lighting the Way to Greener Chemistry: Incandescent Floodlights as a Facile UV Light Source for Classic and Cutting-Edge Photoreactions

Abstract

While ultraviolet light is hailed for its renewability, nontoxicity, and lack of resulting waste products, photochemistry is relatively out of reach for many researchers and industries because conventional ultraviolet radiation sources are not always accessible. For example, the availability of sunlight varies with weather conditions, geographical location, and daylight duration. The use of commercial incandescent light as an alternative to conventional ultraviolet radiation was explored in this article. The classic [2 + 2] photocycloaddition of trans-cinnamic acid was tested under controlled conditions in the solid state, and it was found that 150 W light bulbs provided satisfactory results and 1.5 cm away from the light source was a viable distance for the photoreaction. A [2 + 2] cycloaddition of 10 mg trans-cinnamic acid finished in as few as 4 h. Gram-scale synthesis was also achieved in 40 h by using a 500 W floodlight bulb. The incandescent floodlight also effectively facilitated a cutting-edge photopolymerization in 24 h to produce a two-dimensional (2D) polymer. The use of reliable, inexpensive, and nonhazardous incandescent light in place of sunlight or even ultraviolet lamps for certain photoreactions will allow for the wider study and development of photochemistry.

Size Matters: [2 + 2] Photoreactivity In Macro- and Microcrystalline Salts of 4-Aminocinnamic Acid

“…Incomplete photoconversion was confirmed also by FTIR spectroscopy, as evidenced by residual peaks at 980 (C–H CC out-of-plane bending), 1640 (CC stretching), and 1700 cm –1 (conjugated CO stretching) present in the irradiated sample (see Figure SI-3); − , a shoulder at 1725 cm –1 , due to the partial deconjugation of the carbonyl group, can also be detected in the spectrum.…”

Size Matters: [2 + 2] Photoreactivity In Macro- and Microcrystalline Salts of 4-Aminocinnamic Acid

“…Incomplete photoconversion was confirmed also by FTIR spectroscopy, as evidenced by residual peaks at 980 (C–H CC out-of-plane bending), 1640 (CC stretching), and 1700 cm –1 (conjugated CO stretching) present in the irradiated sample (see Figure SI-3); − , a shoulder at 1725 cm –1 , due to the partial deconjugation of the carbonyl group, can also be detected in the spectrum.…”

Furfural-Derived Diacid Prepared by Photoreaction for Sustainable Materials Synthesis

“…The parallel CC double bonds and a distance of 3.73 Å between them in the FAA crystal make it a good candidate for [2 + 2] photosynthesis (Figure ). ,,,− Our group applied blacklight UV irradiation to the FAA crystalline powder in a slurry reaction to synthesize this diacid building block stereospecifically in 95% isolated yield within 12 h. Only one of the six stereoisomers of the head-to-head dimers was generated (SI) because a solid-state photoreaction normally proceeds by the pathway with the smallest movement of atoms. The photoproduct CBDA-2 , cis -3,4-di­(furan-2-yl)­cyclobutane-1,2-dicarboxylic acid, was fully characterized by several different methods including NMR spectra (SI Figure 3.1).…”

Photo- vs Mechano-Induced Polymorphism and Single Crystal to Single Crystal [2 + 2] Photoreactivity in a Bromide Salt of 4-Amino-Cinnamic Acid

“…Photochemical behavior of [ 1 H]Br form B was also investigated in polycrystalline samples. Upon overnight irradiation, both the FTIR − and FT-Raman − spectra (see SI) showed changes consistent with completion of the [2 + 2] photodimerization: the marker bands of the olefinic moiety disappeared, while those assignable to the dimer (α-truxillic acid derivative) were detected. The occurrence of the reaction was also confirmed by 1 H NMR solution spectroscopy, which showed unequivocally the disappearance of the olefinic peaks and the emergence of cyclobutane protons (see SI).…”

Size Matters: [2 + 2] Photoreactivity In Macro- and Microcrystalline Salts of 4-Aminocinnamic Acid

“…Incomplete photoconversion was confirmed also by FTIR spectroscopy, as evidenced by residual peaks at 980 (C–H CC out-of-plane bending), 1640 (CC stretching), and 1700 cm –1 (conjugated CO stretching) present in the irradiated sample (see Figure SI-3); − , a shoulder at 1725 cm –1 , due to the partial deconjugation of the carbonyl group, can also be detected in the spectrum.…”

Furfural-Derived Diacid Prepared by Photoreaction for Sustainable Materials Synthesis

“…The parallel CC double bonds and a distance of 3.73 Å between them in the FAA crystal make it a good candidate for [2 + 2] photosynthesis (Figure ). ,,,− Our group applied blacklight UV irradiation to the FAA crystalline powder in a slurry reaction to synthesize this diacid building block stereospecifically in 95% isolated yield within 12 h. Only one of the six stereoisomers of the head-to-head dimers was generated (SI) because a solid-state photoreaction normally proceeds by the pathway with the smallest movement of atoms. The photoproduct CBDA-2 , cis -3,4-di­(furan-2-yl)­cyclobutane-1,2-dicarboxylic acid, was fully characterized by several different methods including NMR spectra (SI Figure 3.1).…”

Photo- vs Mechano-Induced Polymorphism and Single Crystal to Single Crystal [2 + 2] Photoreactivity in a Bromide Salt of 4-Amino-Cinnamic Acid

“…Photochemical behavior of [ 1 H]Br form B was also investigated in polycrystalline samples. Upon overnight irradiation, both the FTIR − and FT-Raman − spectra (see SI) showed changes consistent with completion of the [2 + 2] photodimerization: the marker bands of the olefinic moiety disappeared, while those assignable to the dimer (α-truxillic acid derivative) were detected. The occurrence of the reaction was also confirmed by 1 H NMR solution spectroscopy, which showed unequivocally the disappearance of the olefinic peaks and the emergence of cyclobutane protons (see SI).…”

Size Matters: [2 + 2] Photoreactivity In Macro- and Microcrystalline Salts of 4-Aminocinnamic Acid

“…Incomplete photoconversion was confirmed also by FTIR spectroscopy, as evidenced by residual peaks at 980 (C–H CC out-of-plane bending), 1640 (CC stretching), and 1700 cm –1 (conjugated CO stretching) present in the irradiated sample (see Figure SI-3); − , a shoulder at 1725 cm –1 , due to the partial deconjugation of the carbonyl group, can also be detected in the spectrum.…”

Furfural-Derived Diacid Prepared by Photoreaction for Sustainable Materials Synthesis

“…The parallel CC double bonds and a distance of 3.73 Å between them in the FAA crystal make it a good candidate for [2 + 2] photosynthesis (Figure ). ,,,− Our group applied blacklight UV irradiation to the FAA crystalline powder in a slurry reaction to synthesize this diacid building block stereospecifically in 95% isolated yield within 12 h. Only one of the six stereoisomers of the head-to-head dimers was generated (SI) because a solid-state photoreaction normally proceeds by the pathway with the smallest movement of atoms. The photoproduct CBDA-2 , cis -3,4-di­(furan-2-yl)­cyclobutane-1,2-dicarboxylic acid, was fully characterized by several different methods including NMR spectra (SI Figure 3.1).…”

Photo- vs Mechano-Induced Polymorphism and Single Crystal to Single Crystal [2 + 2] Photoreactivity in a Bromide Salt of 4-Amino-Cinnamic Acid

“…Photochemical behavior of [ 1 H]Br form B was also investigated in polycrystalline samples. Upon overnight irradiation, both the FTIR − and FT-Raman − spectra (see SI) showed changes consistent with completion of the [2 + 2] photodimerization: the marker bands of the olefinic moiety disappeared, while those assignable to the dimer (α-truxillic acid derivative) were detected. The occurrence of the reaction was also confirmed by 1 H NMR solution spectroscopy, which showed unequivocally the disappearance of the olefinic peaks and the emergence of cyclobutane protons (see SI).…”