Bronsted Acid-Catalyzed : Synthesis of Phenanthrenes via Phosphomolybdic Acid as a Catalyst was written by Chen, Yi;Liu, Di;Wang, Rui;Xu, Li;Tan, Jingyao;Shu, Mao;Tian, Lingfeng;Jin, Yuan;Zhang, Xiaoke;Lin, Zhihua. And the article was included in Journal of Organic Chemistry in 2022.Safety of 2-Bromo-4-(trifluoromethyl)benzaldehyde This article mentions the following:
Herein, disclosed a synthetic protocol for the synthesis of phenanthrenes such as I [R = H, Me; R1 = H, Me, OMe, etc.; R2 = H, F, OMe, etc.; R3 = H, OTIPS; R4 = H, F, Cl, etc.] through the CCOM with the inexpensive, nontoxic phosphomolybdic acid as a catalyst. The current annulations could realized carbonyl-olefin, carbonyl-alc., and acetal-alc. in situ CCOM reactions and feature mild reaction conditions, simple manipulation and scalability, making this strategy a promising alternative to the Lewis acid-catalyzed COM reaction. In the experiment, the researchers used many compounds, for example, 2-Bromo-4-(trifluoromethyl)benzaldehyde (cas: 85118-24-7Safety of 2-Bromo-4-(trifluoromethyl)benzaldehyde).
2-Bromo-4-(trifluoromethyl)benzaldehyde (cas: 85118-24-7) belongs to organobromine compounds. Bromine is more electronegative than carbon (2.9 vs 2.5). Consequently, the carbon in a carbon–bromine bond is electrophilic, i.e. alkyl bromides are alkylating agents. The reactivity of organobromine compounds resembles but is intermediate between the reactivity of organochlorine and organoiodine compounds. For many applications, organobromides represent a compromise of reactivity and cost.Safety of 2-Bromo-4-(trifluoromethyl)benzaldehyde
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary