In this study, we report the synthesis of eight Schiff bases (3–10) type N-heterocycle (N-het) using conventional refluxing conditions as well as different eco-friendly techniques such as grinding, thermal fusion, microwave irradiation (MWI) and ultrasound, all of them in the presence of a catalytic amount of acetic acid. These procedures had the additional advantage of being environmentally friendly and high-yield, making these protocols an alternative for Schiff-base syntheses. The obtained Schiff bases were coordinated to palladium, generating new complexes of type [Pd₂Cl₄(N-het)₂]. Complexes [Pd₂Cl₄(5)₂] and [Pd₂Cl₄(9)₂] showed high activity and selectivity for a model Mizoroki–Heck C-C coupling reaction of styrene with iodobenzene and bromobenzaldehydes. All compounds and complexes were evaluated for antifungal activity against clinically important fungi such as Candida albicans and Cryptococcus neoformans. Although the Schiff bases (3–10) showed low antifungal activity against both fungi, some of their palladium complexes such as [Pd₂Cl₄(3)₂], [Pd₂Cl₄(5)₂], [Pd₂Cl₄(8)₂] and [Pd₂Cl₄(10)₂] showed comparatively higher antifungal effects mainly against C. neoformans. The product of the Mizoroki–Heck-type C-C coupling reactions, 4-styrylbenzaldehyde, was isolated and purified to be later used in the synthesis of four new nitrophenylpyrazole derivatives of styrylimine, which also displayed antifungal activity, especially against C. neoformans.

Nitric oxide (NO) insertion into a metalloporphyrin rhodium–carbon bond is observed when crystals of (TPP)Rh(C₆H₄Cl)(CH₂Cl₂)_x (TPP = tetraphenylporphyrinato dianion) are exposed to NO gas over a two week period. The NO-inserted product was identified by X-ray crystallography as (TPP)Rh(ONC₆H₄Cl-o)(CH₂Cl₂)_0.5·(TPP)Rh(C₆H₄Cl-p/m)(CH₂Cl₂)_0.5, in which NO inserted selectively into the ortho-Cl aryl isomer but not into the para-/meta-Cl aryl isomers. Density functional theory calculations predict a higher reactivity for the ortho-Cl isomer and thus provide a rationale for the preferred NO insertion into the potentially more reactive ortho-Cl isomer under our reaction conditions. Whereas NO insertion reactions are well-known for coordination–organometallic compounds, this result represents the first such NO insertion into a metalloporphyrin metal–carbon bond for any metal.