Cobalt-Catalyzed Asymmetric Sequential Hydroboration/Hydrogenation of Internal Alkynes
JacsCobalt-Catalyzed Asymmetric Sequential Hydroboration/Hydrogenation of Internal Alkynes: A highly regio- and enantioselective cobalt-catalyzed hydroboration/hydrogenation of internal alkynes with HBpin and a hydrogen balloon in one pot was developed. A new type of chiral imidazoline iminopyridine (IIP) ligand was introduced for the first time in this novel and efficient strategy. This protocol used relatively simple and available starting materials with good functional group tolerance to construct more valuable chiral secondary organoboronates. (Source: Organometallic Current)
Source: Organometallic Current - October 25, 2017 Category: Chemistry Tags: Co catalyzed Hydroboration Hydrogenation Source Type: blogs
A Mild Hydroaminoalkylation of Conjugated Dienes Using a Unified Cobalt and Photoredox Catalytic System
JacsA Mild Hydroaminoalkylation of Conjugated Dienes Using a Unified Cobalt and Photoredox Catalytic System: Metallo-photoredox catalysis has redefined the available bond disconnections in the synthetic arsenal. By harnessing the one-electron chemistry of photoredox catalysis in tandem with low-valent cobalt catalysts, new methods by which functionalities may be stitched together become available. Herein we describe the coupling of photoredox-generated α-amino radical species with conjugated dienes using a unified cobalt and iridium catalytic system in order to access a variety of useful homoallylic amines from simple com...
Source: Organometallic Current - October 25, 2017 Category: Chemistry Tags: Co catalyzed Photoredox Catalysis Source Type: blogs
Cobalt versus Osmium: Control of Both trans and cis Selectivity in Construction of the EFG Rings of Pectenotoxin 4
AngewchemCobalt versus Osmium: Control of Both trans and cis Selectivity in Construction of the EFG Rings of Pectenotoxin 4: Catalytic oxidative cyclisation reactions have been employed for the synthesis of the E and F rings of the complex natural product target pectenotoxin 4. The choice of metal catalyst (cobalt‐ or osmium‐based)... (Source: Organometallic Current)
Source: Organometallic Current - October 23, 2017 Category: Chemistry Tags: Co catalyzed Natural products Source Type: blogs
Naturopaths: Able to turn even Epsom salt potentially deadly
Naturopathy and naturopaths are a fairly frequent topic on this blog —and for very good reason. If there is an example of a pseudomedical " discipline " that has been gaining undeserved " respectability, " it ' s naturopathy. It ' s licensed in all too many states, and physicians who have fallen under the spell of so-called " integrative medicine, " a specialty that rebrands science-based lifestyle medical interventions as somehow " alternative " or " integrative " and uses them as a vessel to " integrate " quackery into medicine, seem to have a special affinity for naturopaths. Indeed, so common has the presence of natu...
Source: Respectful Insolence - October 6, 2017 Category: Surgery Authors: oracknows Source Type: blogs
Synthesis of Bicyclo[n.1.0]alkanes by a Cobalt ‐Catalyzed Multiple C(sp3)−H Activation Strategy
AngewchemSynthesis of Bicyclo[n.1.0]alkanes by a Cobalt ‐Catalyzed Multiple C(sp3)−H Activation Strategy: A cobalt ‐catalyzed dual C(sp3)−H activation strategy has been developed and it provides a novel strategy for the synthesis of bicyclo[4.1.0]heptanes and bicyclo[3.1.0]hexanes. A key to the success of this... (Source: Organometallic Current)
Source: Organometallic Current - September 8, 2017 Category: Chemistry Tags: Co catalyzed sp3 C-H Activation Source Type: blogs
A Role for Magnetism in the ED
Children have this strange predilection for placing small objects in body cavities and orifices. Besides putting foreign bodies in their mouths, an act that often leads to ingestion or aspiration, the ear canals and nares are their favorite locations for depositing plastic beads, toy parts, paper materials, small vegetables, jewelry, screws, and nails, and that frequently brings them to the emergency department. Unsuccessful attempts to remove the foreign bodies in the ED lead to a consultation or referral to an ENT specialist. The timing, technique, and tools used to remove a foreign body will depend on the anatom...
Source: M2E Too! Mellick's Multimedia EduBlog - September 1, 2017 Category: Emergency Medicine Tags: Blog Posts Source Type: blogs
Cobalt-Catalyzed Carbonylative Cross-Coupling of Alkyl Tosylates and Dienes: Stereospecific Synthesis of Dienones at Low Pressure
JacsCobalt-Catalyzed Carbonylative Cross-Coupling of Alkyl Tosylates and Dienes: Stereospecific Synthesis of Dienones at Low Pressure: Despite advances in organometallic cross-coupling of alkyl electrophiles, there are few stereoselective reactions of chiral, nonracemic substrates. Herein we report a stereospecific carbonylative coupling of alkyl tosylates and dienes producing enantioenriched dienones. This catalytic process proceeds under low pressure and mild conditions using a simple cobalt catalyst and extends to diverse tosylate and diene coupling partners. (Source: Organometallic Current)
Source: Organometallic Current - August 31, 2017 Category: Chemistry Tags: Carbonylation Co catalyzed Source Type: blogs
The challenges of formulating a natural cosmetic line
Conclusion
While creating truly natural products can be challenging, it can be done demonstrated by successful brands like Burts Bees, Aveeno, and Physicians Formula. It requires you to figure out what your consumer believes is natural then make products that adhere to those natural standards. After that, success is just a matter of good marketing. (Source: thebeautybrains.com)
Source: thebeautybrains.com - August 20, 2017 Category: Consumer Health News Authors: Perry Romanowski Tags: Natural cosmetics Source Type: blogs
Tailor ‐made Molecular Cobalt Catalyst System for the Selective Transformation of Carbon Dioxide to Dialkoxymethane Ethers
: Herein a non ‐precious transition‐metal catalyst system for the selective synthesis of dialkoxymethane ethers from carbon dioxide and molecular hydrogen is presented. The development of a tailored catalyst... (Source: Organometallic Current)
Source: Organometallic Current - August 1, 2017 Category: Chemistry Tags: Co catalyzed Source Type: blogs
Full Selectivity Control in Cobalt(III) ‐Catalyzed C−H Alkylations by Switching of the C−H Activation Mechanism
AngewchemFull Selectivity Control in Cobalt(III) ‐Catalyzed C−H Alkylations by Switching of the C−H Activation Mechanism: Selectivity control in hydroarylation ‐based C−H alkylation has been dominated by steric interactions. A conceptually distinct strategy that exploits the programmed switch in the C−H activation mechanism... (Source: Organometallic Current)
Source: Organometallic Current - July 25, 2017 Category: Chemistry Tags: C-H alkylation Co catalyzed Source Type: blogs
A Convergent Synthesis of Functionalized Alkenyl Halides through Cobalt(III) ‐Catalyzed Three‐Component C−H Bond Addition
AngewchemA Convergent Synthesis of Functionalized Alkenyl Halides through Cobalt(III) ‐Catalyzed Three‐Component C−H Bond Addition: A CoIII ‐catalyzed three‐component coupling of C(sp2)−H bonds, alkynes, and halogenating agents to give alkenyl halides is reported. This transformation proceeds with high regio‐ and diastereoselectivity,... (Source: Organometallic Current)
Source: Organometallic Current - July 19, 2017 Category: Chemistry Tags: Co catalyzed Multicomponent Rxn Source Type: blogs
Cobalt Catalysis for Enantioselective Cyclobutanone Construction
JacsCobalt Catalysis for Enantioselective Cyclobutanone Construction: Over the past 40 years, intramolecular hydroacylation has favored five-membered rings, in preference to four membered rings. Herein, we report a catalyst derived from earth-abundant cobalt that enables preparation of cyclobutanones, with excellent regio-, diastereo-, and enantiocontrol, under mild conditions. (Source: Organometallic Current)
Source: Organometallic Current - July 14, 2017 Category: Chemistry Tags: Co catalyzed Enantioselective Source Type: blogs
Highly Enantioselective Cobalt-Catalyzed Hydrosilylation of Alkenes
JacsHighly Enantioselective Cobalt-Catalyzed Hydrosilylation of Alkenes: A cobalt-catalyzed highly Markovnikov-type and enantioselective hydrosilylation of alkenes is developed for the efficient synthesis of valuable chiral dihydrosilanes. This protocol is operationally simple and atom-economy, and using relatively simple and readily available starting materials. (Source: Organometallic Current)
Source: Organometallic Current - July 12, 2017 Category: Chemistry Tags: Co catalyzed Hydrosilylation Source Type: blogs
A Biomass ‐Derived Non‐Noble Cobalt Catalyst for Selective Hydrodehalogenation of Alkyl and (Hetero)Aryl Halides
AngewchemA Biomass ‐Derived Non‐Noble Cobalt Catalyst for Selective Hydrodehalogenation of Alkyl and (Hetero)Aryl Halides: Hydrodehalogenation is a straightforward approach for detoxifications of harmful anthropogenic organohalide ‐based pollutants, as well as removal of halide protecting groups used in multistep syntheses.... (Source: Organometallic Current)
Source: Organometallic Current - July 4, 2017 Category: Chemistry Tags: Co catalyzed Dehalogenation Source Type: blogs
