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We report the synthesis and characterization of homoleptic borane adducts of hexacyanoferrate( ii ). Borane coordination blueshifts d–d transitions and CN IR and Raman frequencies. Control over redox properties is established with respect to borane Lewis acidity, reflected in peak anodic potential shifts per borane of +250 mV for BPh 3 and +350 mV for B(C 6 F 5 ) 3 . Electron transfer from [Fe(CN-B(C 6 F 5 ) 3 ) 6 ] 4− to photogenerated [Ru(2,2′-bipyridine) 3 ] 3+ is very rapid, consistent with voltammetry data. Coordination by Lewis acids provides an avenue for selective modification of the electronic structures and electrochemical properties of cyanometalates. 

A concise and stereoselective total synthesis of the clinically relevant tricyclic prostaglandin D₂metabolite (tricyclic‐PGDM) methyl ester in racemic form was accomplished in eight steps from a readily available known cyclopentene‐diol derivative. The synthesis features a nickel‐catalyzed Ueno–Stork‐type dicarbofunctionalization to generate two consecutive stereocenters, a palladium‐catalyzed carbonylative spirolactonization to build the core oxaspirolactone, and aZ‐selective cross‐metathesis to introduce the (Z)‐3‐butenoate side chain, a group challenging to introduce through traditional Wittig protocols and troublesome for the two previous total syntheses. A generalZ‐selective cross‐metathesis protocol to construct (Z)‐β,γ‐unsaturated esters was also developed that has broad functional group tolerance and high stereoselectivity. Additionally, our synthesis already accumulated 75 mg of valuable material for an¹⁸O‐tricyclic‐PGDM‐based assay used in clinical settings for inflammation.

 

A concise and stereoselective total synthesis of the clinically relevant tricyclic prostaglandin D₂metabolite (tricyclic‐PGDM) methyl ester in racemic form was accomplished in eight steps from a readily available known cyclopentene‐diol derivative. The synthesis features a nickel‐catalyzed Ueno–Stork‐type dicarbofunctionalization to generate two consecutive stereocenters, a palladium‐catalyzed carbonylative spirolactonization to build the core oxaspirolactone, and aZ‐selective cross‐metathesis to introduce the (Z)‐3‐butenoate side chain, a group challenging to introduce through traditional Wittig protocols and troublesome for the two previous total syntheses. A generalZ‐selective cross‐metathesis protocol to construct (Z)‐β,γ‐unsaturated esters was also developed that has broad functional group tolerance and high stereoselectivity. Additionally, our synthesis already accumulated 75 mg of valuable material for an¹⁸O‐tricyclic‐PGDM‐based assay used in clinical settings for inflammation.

 

Small‐angle scattering measurements of complex macromolecules in solution are used to establish relationships between chemical structure and conformational properties. Interpretation of the scattering data requires an inverse approach where a model is chosen and the simulated scattering intensity from that model is iterated to match the experimental scattering intensity. This raises challenges in the case where the model is an imperfect approximation of the underlying structure, or where there are significant correlations between model parameters. We examine three bottlebrush polymers (consisting of polynorbornene backbone and polystyrene side chains) in a good solvent using a model commonly applied to this class of polymers: the flexible cylinder model. Applying a series of constrained Monte‐Carlo Markov Chain analyses demonstrates the severity of the correlations between key parameters and the presence of multiple close minima in the goodness of fit space. We demonstrate that a shape‐agnostic model can fit the scattering with significantly reduced parameter correlations and less potential for complex, multimodal parameter spaces. We provide recommendations to improve the analysis of complex macromolecules in solution, highlighting the value of Bayesian methods. This approach provides richer information for understanding parameter sensitivity compared to methods which produce a single, best fit.