Latent Functions and Applications of Cytochrome P450 Monooxygenases from : A Novel Biocatalyst for 14α-Hydroxylation of Testosterone.

Cytochrome P450 monooxygenases (P450s) are ubiquitous enzymes with high availability and diversity in nature. Fungi provide a diverse and complex array of P450s, and these enzymes play essential roles in various secondary metabolic processes. Besides the physiological impacts of P450s on fungal life, their versatile functions are attractive for use in advanced applications of the biotechnology sector.

Reactivity of a Dinuclear Pd Complex [Pd(μ-PPh)(μ-OAc)(PPh)] with PPh: Implications for Cross-Coupling Catalysis Using the Ubiquitous Pd(OAc)/nPPh Catalyst System.

[Pd (μ-PPh)(μ-OAc)(PPh)] is the reduction product of Pd(OAc)(PPh), generated by reaction of 'Pd(OAc)' with two equivalents of PPh. Here, we report that the reaction of [Pd (μ-PPh)(μ-OAc)(PPh)] with PPh results in a nuanced disproportionation reaction, forming [Pd(PPh)] and a phosphinito-bridged Pd-dinuclear complex, namely [Pd (μ-PPh){κ-P,O-μ-P(O)Ph}(κ-PPh)]. The latter complex is proposed to form by abstraction of an oxygen atom from an acetate ligand at Pd.

A Dichotomy in Cross-Coupling Site Selectivity in a Dihalogenated Heteroarene: Influence of Mononuclear Pd, Pd Clusters, and Pd Nanoparticles-the Case for Exploiting Pd Catalyst Speciation.

Site-selective dihalogenated heteroarene cross-coupling with organometallic reagents usually occurs at the halogen proximal to the heteroatom, enabled by intrinsic relative electrophilicity, particularly in strongly polarized systems. An archetypical example is the Suzuki-Miyaura cross-coupling (SMCC) of 2,4-dibromopyridine with organoboron species, which typically exhibit C2-arylation site-selectivity using mononuclear Pd (pre)catalysts. Given that Pd speciation, particularly aggregation, is known to lead to the formation of catalytically competent multinuclear Pd species, the influence of these species on cross-coupling site-selectivity remains largely unknown.

Synthesis of 1-indanols and 1-indanamines by intramolecular palladium(0)-catalyzed C(sp3)-H arylation: impact of conformational effects.

A range of valuable 1-indanols and 1-indanamines containing a tertiary C1 atom were synthesized by intramolecular palladium(0)-catalyzed C(sp(3))-H arylation, despite unfavorable steric interactions. The efficiency of the reaction was found to correlate with the degree of substitution at C2, as expected from the Thorpe-Ingold effect. Additionally, the nature of the heteroatomic substituent at C1 had a marked influence on the diastereoselectivity at C1 and C2; indeed, 1-indanols and 1-indanamines were obtained with the opposite relative configuration.

New preparation of TMPZnCl·LiCl by Zn insertion into TMPCl. Application to the functionalization of dibromodiazines.

A practical zinc insertion starting from cheap commercial zinc powder and TMPCl (1-chloro-2,2,6,6-tetramethylpiperidine) allows a fast and efficient synthesis of the zinc base TMPZnCl·LiCl under mild conditions in high yields. This base is kinetically highly active and was used for the regio- and chemoselective functionalization of dibromodiazines (pyridazines and pyrazines).