Ir 435

Samples were scanned in the range of 4000–500 cm⁻¹ at ambient temperature using an IR spectrophotometer (Shimadzu IR-435, Kyoto, Japan), after compression into a transparent disc with KBr 10,000 to 15,000 pounds/inch²). IR spectra were recorded and analyzed.

All reactions were performed under an N₂ atmosphere. Unless otherwise stated, all reagents were purchased from commercial suppliers and used without further purification. Organic solvents were concentrated under reduced pressure using a rotary evaporator or oil pump. Flash column chromatography was performed using Qingdao Haiyang flash silica gel (200–300 mesh). Meting points were measured on a Yanagimoto apparatus and uncorrected. Infrared spectra were recorded using a Shimadzu IR-435 instrument with KBr plates. ¹H- and ¹³C-NMR spectra were obtained on Bruker DPX 300 spectrometer (Bruker Biospin Co., Stuttgart, Germany) with CDCl₃ as the solvent and TMS as the internal standard. HR-MS were obtained on a Brüker Apex II mass spectrometer using nitrobenzoyl alcohol and sodium chloride as matrix (ThermoFisher scientific Inc., Waltham, MA, USA).

Samples (2–4 mg) were separately mixed with about 400 mg of dry potassium bromide powder and compressed into transparent disc under pressure of 10 000 to 15 000 pounds/inch²; and scanned in the range of 4000–500 cm⁻¹ at ambient temperature using IR spectrophotometer (Shimadzu IR-435, Kyoto, Japan) their IR spectra were recorded and analyzed.