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2. Cheletropic reaction - Wikipedia

   en.wikipedia.org/wiki/Cheletropic_reaction

   A singlet carbene contains an empty p orbital and a roughly sp 2 hybrid orbital that has two electrons. Singlet carbenes add stereospecifically to alkenes, and alkene stereochemistry is retained in the cyclopropane product. [1] The mechanism for addition of a carbene to an alkene is a concerted [2+1] cycloaddition (see figure).

3. Carbene - Wikipedia

   en.wikipedia.org/wiki/Carbene

   Carbene radicals, in which the carbene is bonded to an open-shell metal with the carbene carbon possessing a radical character. Carbene radicals have features of both Fischer and Schrock carbenes, but are typically long-lived reaction intermediates. The "second generation" of the Grubbs catalysts for alkene metathesis features an NHC ligand.

4. Transition metal carbene complex - Wikipedia

   en.wikipedia.org/wiki/Transition_metal_carbene...

   A transition metal carbene complex is an organometallic compound featuring a divalent carbon ligand, itself also called a carbene. [1] Carbene complexes have been synthesized from most transition metals and f-block metals , [ 2 ] using many different synthetic routes such as nucleophilic addition and alpha-hydrogen abstraction. [ 1 ]

5. Carbene dimerization - Wikipedia

   en.wikipedia.org/wiki/Carbene_dimerization

   In this reaction type either the two carbenic intermediates react or a carbenic intermediate reacts with a carbene precursor. [1] An early pioneer was Christoph Grundmann reporting on a carbene dimerisation in 1938. [2] In the domain of persistent carbenes the Wanzlick equilibrium describes an equilibrium between a carbene and its alkene.

6. Carbene radical - Wikipedia

   en.wikipedia.org/wiki/Carbene_radical

   Bonding scheme of carbene radical complexes as compared to Schrock and Fischer-type carbene complexes. Carbene radicals are a special class of organometallic carbenes.The carbene radical can be formed by one-electron reduction of Fischer-type carbenes using an external reducing agent, or directly upon carbene formation at an open-shell transition metal complex (in particular low-spin cobalt(II ...

7. Olefin metathesis - Wikipedia

   en.wikipedia.org/wiki/Olefin_metathesis

   Hérisson and Chauvin first proposed the widely accepted mechanism of transition metal alkene metathesis. [12] The direct [2+2] cycloaddition of two alkenes is formally symmetry forbidden and thus has a high activation energy. The Chauvin mechanism involves the [2+2] cycloaddition of an alkene double bond to a transition metal alkylidene to ...

8. How to watch the ‘Rudolph the Red-Nosed Reindeer’ NBC ...

   www.aol.com/entertainment/rudolph-red-nosed...

   After Rudolph’s initial success, Rankin/Bass made sequels to his story, including Rudolph’s Shiny New Year, where Santa tasks Rudolph with finding the Baby New Year before time is frozen ...

9. Addition reaction - Wikipedia

   en.wikipedia.org/wiki/Addition_reaction

   In organic chemistry, an addition reaction is an organic reaction in which two or more molecules combine to form a larger molecule called the adduct. [ 1 ] [ 2 ] An addition reaction is limited to chemical compounds that have multiple bonds .