Photochemistry of 4H,7H-Benzo

Area of Science:

• Organic Photochemistry
• Synthetic Organic Chemistry

Background:

• The synthesis and photochemical behavior of novel organic compounds are crucial for developing new materials and reaction pathways.
• Understanding photoinduced transformations provides insights into reaction mechanisms and product selectivity.

Purpose of the Study:

• To synthesize compound 1 and investigate its photochemical reactivity under different irradiation conditions.
• To explore the formation of dimers and cyclobutane adducts from compound 1.
• To characterize the products of these photochemical transformations.

Main Methods:

• Synthesis of the title compound 1 starting from 1, 2-bis(2-hydroxyethyl)benzene.
• Photochemical irradiation of compound 1 in acetonitrile (CH3CN) at 350 nm.
• Photochemical irradiation of compound 1 in the presence of tetrachloroethene at wavelengths greater than 390 nm.
• Characterization of reaction products using spectroscopic techniques.

Main Results:

• Compound 1 was successfully synthesized.
• Irradiation of compound 1 in CH3CN at 350 nm selectively produced the all-cis-dimer 6 in high yield (>90%).
• Irradiation of compound 1 in the presence of tetrachloroethene (>390 nm) selectively yielded the monocyclobuta adduct 8.
• Subsequent irradiation of adduct 8 resulted in a 4:1 mixture of biscyclobuta derivatives 9 and 10.

Conclusions:

• Compound 1 exhibits distinct photochemical reactivity depending on the irradiation wavelength and reaction medium.
• Selective formation of dimers and cyclobutane adducts is achievable through controlled photochemical conditions.
• The study demonstrates a pathway for the synthesis of complex polycyclic compounds via photoinduced cyclization reactions.