A laboratory experiment that involves the aqueous and solid phase synthesis, characterization, and solvatochromic properties exploration of red complex [Ni(Me[subscript 3]en)(acac)]BPh[subscript 4] has been developed for first-year undergraduates in the College of Chemistry and Chemical Engineering at Xiamen University. In contrast to previously reported synthesis methods (Fukuda, Y. Studies on mixed chelates-II Mixed nickel(II) chelates with "N,N,N',N'"-tetramethylethylenediamine and [beta]-diketones. "J. Inorg. Nucl. Chem." 1972, 34, 2315-2328; Funasako, Y. Thermochromic and solvatochromic Nafion films incorporating cationic metal-chelate complexes. "Chem. Comm" 2013, 49, 4688-4690; Hosokawa, H. Colorimetric Humidity and Solvent Recognition Based on a Cation-Exchange Clay Mineral Incorporating Nickel(II)-Chelate Complexes. "Langmuir" 2015, 31, 13048-13053; Nguyen, T. N. Studies on Mixed Chelates. VII. Mixed Nickel(II) Chelates Containing "N,N'"- or "N,N"-Dialkylethylenediamines and Acetylacetone. "Bull. Chem. Soc. Jpn." 1977, 50 (1), 154-157; Wei, X. J. Vis-Spectrum Investigation of Thermo-Solvatochromic Behaviors of a Mixed Diamine and [beta]-Diketonate Ligand Ni(II) Complex in Different Alcoholic Solutions. "Acta Phys.-Chim. Sin." 2009, 25 (7), 1449-1454; "Inorganic and Analytical Chemistry Experiment Test of The 10th Chinese National Undergraduate Chemistry Laboratory Tournament" https://chemlabs.nju.edu.cn/DFS/file/2019/08/26/20190826132901247mmvyr5.pdf?iid=2382 (accessed November 2023).), which using a large amount of organic solvents, the aqueous and solid phase synthesis methods described here are remarkably green, environmentally friendly, high efficiency and highly reproducible, and the complex [Ni(Me[subscript 3]en)(acac)]BPh[subscript 4] showing a remarkable reversible solvatochromic phenomenon, so this experiment is very suitable as a classroom demonstration for first-year undergraduates in inorganic chemistry or general chemistry. By performing this experiment, students will gain experience in solid phase synthesis, purification, and UV--vis characterization of the complex. In addition, students will gain appreciation of how solvatochromism and thermochromism (in acetone) of the complex [Ni(Me[subscript 3]en)(acac)]BPh[subscript 4] and their mechanisms, and progress in the understanding of the effect of the configuration of a complex on crystal field splitting, and the effect of crystal field splitting on color.