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In a standard two-ligand reductive elimination, two metal-bound anionic fragments couple to form a bond while metal oxidation state decreases by two. The reacting ligands commonly need adjacent positions; favorable bond formation and metal reduction energetics determine whether the formal step actually occurs.
Conjugate addition attacks a beta position in a conjugated electrophile and redistributes pi bonding, often generating an enolate. proton transfer then supplies a saturated carbonyl product.
A condensation reaction joins molecular units while eliminating a small molecule such as water or an alcohol. Formation of an ester from a carboxylic acid and an alcohol is a familiar example.
The term classifies the overall transformation, not one universal mechanism. In polycondensation, repeated joining can build a polymer while small molecules are released. An aldol condensation combines carbon-carbon bond formation with a subsequent elimination, so its full outcome must be distinguished from the initial aldol reaction.
Methyl abstraction transfers a metal-bound methyl group to an electrophile. A trityl cation can convert a neutral metallocene dimethyl into a cationic monomethyl, forming and opening a site for an alkene ligand.
Beta-hydride elimination transfers hydrogen from the beta carbon of a metal-bound alkyl to the metal while forming an alkene. It can release a growing polymer chain and compete with migratory insertion. Its accessibility depends on geometry, available sites and bond energetics.
Desilylation removes a silyl group. Attack by a nucleophile at silicon can pass through a pentacoordinate silicon arrangement before Si–O cleavage; the liberated oxygen may be trapped by a new electrophile.
An anti addition places the two newly attached groups on opposite faces of an unsaturated unit. Backside opening of a cyclic bromonium ion is a standard example.
A syn addition attaches both new groups from the same face of an unsaturated unit. Formation of a cyclic osmate ester explains syn dihydroxylation.
Dihydroxylation installs hydroxyl groups on adjacent alkene carbons. osmium tetroxide gives a syn addition pathway through a cyclic osmate ester.
Hydroalumination adds an Al–H equivalent across an unsaturated bond. Syn and directed trans pathways give different alkenyl-aluminium geometries; protonolysis can preserve that stereochemical information.
A reaction that joins unsaturated components while forming a ring and new sigma bonds. Its transition-state entropy and activation volume depend on both molecular reorganization and the surrounding medium.
Loss of carbon dioxide from a compound. Malonic-acid derivatives can decarboxylate through cyclic proton-transfer/bond-cleavage arrangements that generate a carbonyl-stabilized product.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact