08-01-2021-0248 - So go ahead! Donate a pair of electrons to the phosphorus. It can't help itself, because of the strength of the P-O bond that forms.

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So go ahead! Donate a pair of electrons to the phosphorus. It can't help itself, because of the strength of the P-O bond that forms.

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Reactions/Addition_Reactions/Addition_to_Carbonyls/Ylide_Addition

Sulfur ylides are also good nucleophiles for aldehydes and ketones. However, the unusual stability of the phosphorus-oxygen bond does not have a similar analogue in sulfur chemistry.

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Reactions/Addition_Reactions/Addition_to_Carbonyls/Ylide_Addition

Show, with arrows, the mechanism for formation of the sulfur ylide

above.

Once formed, sulfur ylides react with aldehydes or ketones. Like phosphorus ylides, the reaction starts out just like any other nucleophile, but a second step takes a very different direction. Epoxides are formed in these reactions, and the original sulfur compound (a thioether) is regenerated.

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Reactions/Addition_Reactions/Addition_to_Carbonyls/Ylide_Addition
Phosphonium Ylide

Phosphonium ylides are readily available by reaction of alkyl halides or sulfonates with triarylphosphane to form phosphonium salts which are deprotonated with a base (BuLi, NaH, CaH2,14 KOtBu).

From: Organic Syntheses Based on Name Reactions (Third Edition), 2012
Related terms:
Anion
Ligand
Ester
Aldehyde
Arsonium
Ylide
Phosphonium
Alkene
Wittig Reaction
[Alpha]
View all Topics

https://www.sciencedirect.com/topics/chemistry/phosphonium-ylide
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A Phosphonium Ylide as an Ionic Nucleophilic Catalyst for Primary Hydroxyl Group Selective Acylation of Diols

Yasunori Toda*,
Tomoyuki Sakamoto,
Yutaka Komiyama,
Ayaka Kikuchi, and
Hiroyuki Suga*
View Author Information
Cite this: ACS Catal. 2017, 7, 9, 6150–6154
Publication Date:August 10, 2017

https://doi.org/10.1021/acscatal.7b02281
Copyright © 2017 American Chemical Society
RIGHTS & PERMISSIONS

https://pubs.acs.org/doi/10.1021/acscatal.7b02281

Vinylphosphonium and 2-aminovinylphosphonium salts – preparation and applications in organic synthesis
Anna Kuźnik,1,2,§ Roman Mazurkiewicz,1,2 and Beata Fryczkowska3
David Yu-Kai Chen, Associate Editor
Author information Article notes Copyright and License information Disclaimer
PMCID: PMC5753072
PMID: 29564008
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5753072/

ol Divers

. 2010 Aug;14(3):569-74. doi: 10.1007/s11030-009-9188-y. Epub 2009 Aug 13.
One-pot synthesis of 4-arylquinolines from aromatic aminoketones and vinylphosphonium salts
Sakineh Asghari 1, Mohammad Qandalee, Zahra Naderi, Zahra Sobhaninia
Affiliations expand
PMID: 19680770
DOI: 10.1007/s11030-009-9188-y
https://pubmed.ncbi.nlm.nih.gov/19680770/


EXPERIMENTAL AND THEORETICAL STUDY OF STABLE PHOSPHORUS YLIDES DERIVED FROM INDAZOLE IN THE PRESENCE OF DIFFERENT DIALKYL ACETYELENEDICARBOXYLATES: FURTHER INSIGHTS INTO THE REACTION MECHANISM

MOHAMMAD ZAKARIANEZHAD1, BATOUL MAKIABADI2 AND MOTAHARE SHOOL1

1 Department of Chemistry, Payam Noor University, Tehran, Iran
2 Department of Chemical Engineering, Sirjan University of Technology, Sirjan, Iran
* e-mail: m.zakarianejad@yahoo.com

https://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072016000200016

While triphenylalkylphosphonium salts as ylide precursors unambiguously lead to alkylidenetriphenylphosphoranes,

https://www.sciencedirect.com/topics/chemistry/phosphonium-ylide

A great variety of bases has been used to generate ylides from the corresponding phosphonium salts: various nitrogen bases, alkoxides, alkali metal hydrides, carbanionic bases, alkali metal hydroxides and carbonates, ethylene oxides, basic ylides and others.31,35,36

The use of sodium amide proved to be very successful in the synthesis of nonstabilized ylides free from lithium salts.35,56The reaction is usually carried out in liquid ammonia, but also a suspension of so- dium amide in benzene or THF can be used. Whereas alkyltriarylphosphonium salts are deprotonated in liquid ammonia, in the case of the corresponding tetraalkyl compounds boiling THF is necessary.48 Mix- tures of dry phosphonium salt and powdered sodium amide can be stored indefinitely and hence provide ‘instant ylide’ mixtures.57 Upon addition of an ethereal solvent the ylide is quantitatively generated.

Conversion of phosphonium salts to salt-free solutions of ylides can also be effected with sodium bis(trimethylsilyl)amide 58

https://www.sciencedirect.com/topics/chemistry/phosphonium-ylide

Phosphoacyl Functions and Their As, Sb, and Bi Analogs☆

L. Weber, in Reference Module in Chemistry, Molecular Sciences and Chemical Engineering, 2013
Methylene phosphenium salts

The C-borylated P-chloro phosphonium ylide 184, which is a suitable precursor for methylene phosphenium salt 151, was conveniently accessible by chlorination of the (Pri2N)2PCH2BMes2 with carbon tetrachloride in toluene in 79% yield. A stoichiometric amount of gallium trichloride was added to abstract the chloride ion from ylide 184 at − 80 ᵒC in dichloromethane solution yielding salt 185 as the initial product. Above − 40 ᵒC salt 185 experienced an exchange of substituents between the boron and the phosphorus atoms. After work up methylene phosphenium salt 151 was obtained as white crystals in 73% yield (Scheme 62).48

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