Photoactivated Pyridine Directed Fluorination through Hydrogen Atom Transfer.

We have established hydrogen atom transfer (HAT) as the key player in a directed, photopromoted fluorination of pyridylic groups. The Lewis basic pyridyl nitrogen directs amine radical dication propagated HAT and Selectfluor fluorination of various ortho substituents in a highly regioselective manner with little to no side product formation. A variety of pyridines and quinolines were employed to showcase the directing capability of the nitrogen atom. Additionally, both experimental and computational data are provided that illuminate how this mechanism differs from and complements prior work in the area.

C-C Bond Activation and Demethylenation of Epoxides by Amine Radical Dications.

In this note, we explore a unique reactivity pattern that involves a rare radical-based C-C bond scission of epoxides followed by demethylenation. The reaction is accomplished by Selecfluor and its radical dication working in tandem; a mechanism supported by experiment and DFT calculations is proposed that involves the generation and identification of a key reactive intermediate. The reaction seems to be fairly general for 1,1-disubstituted epoxides.

An Electrochemical Approach to Directed Fluorination.

Electrosynthesis has made a revival in the field of organic chemistry and, in particular, radical-mediated reactions. Herein, we report a simple directed, electrochemical C-H fluorination method. Employing a dabconium mediator, commercially available Selectfluor, and RVC electrodes, we provide a range of steroid-based substrates with competent regioselective directing groups, including enones, ketones, and hydroxy groups, as well as never reported before lactams, imides, lactones, and esters.

Hydroxy-directed fluorination of remote unactivated C(sp3)-H bonds: a new age of diastereoselective radical fluorination.

We report a photochemically induced, hydroxy-directed fluorination that addresses the prevailing challenge of high diastereoselectivity in this burgeoning field. Numerous simple and complex motifs showcase a spectrum of regio- and stereochemical outcomes based on the configuration of the hydroxy group. Notable examples include a long-sought switch in the selectivity of the refractory sclareolide core, an override of benzylic fluorination, and a rare case of 3,3'-difluorination. Furthermore, calculations illuminate a low barrier transition state for fluorination, supporting our notion that alcohols are engaged in coordinated reagent direction. A hydrogen bonding interaction between the innate hydroxy directing group and fluorine is also highlighted for several substrates with 19F-1H HOESY experiments, calculations, and more.

Boston bombings: a surgical view of lessons learned from combat casualty care and the applicability to Boston's terrorist attack.

The Boston bombing incident was a recent civilian mass casualty terrorist event that demonstrated effective transfer of the lessons of combat casualty care to inform effective civilian medical care. Thirty-nine patients were seen at Brigham and Women's Hospital and thirteen patients received emergency surgery in the first few hours after the event. The subsequent management, total hospital days 181, total number of operative procedures 72, and discharging service listing of these thirteen patients illustrate the intensive surgical resources necessary after a civilian bomb attack. Plastic surgery played a role in the multidisciplinary collaboration of the limb salvage efforts and this role can inform the importance of other plastic surgery contributions within mass casualty surgical management. We believe that prepositioned collaborative relationships of plastic surgery, vascular surgery, trauma surgery and orthopedic surgery may offer a model of collaboration for limb salvage that can be applied in military and mass casualty medical care if resources permit. In this attack, effective use of tourniquets was implemented by prehospital medical providers that saved lives and limbs and these actions reaffirm the important lessons learned from combat casualty care. Unfortunately, it is likely that more centers will deal with similar events in the future and it is imperative that we as a community of providers take what lessons we can from battlefield medicine and that we collectively prepare for and engage this future.