Arbuzov Reaction Michaelis-Arbuzov Reactio

The Michaelis–Arbuzov reaction (also called the Arbuzov reaction) is the chemical reaction of a trialkyl phosphite and an alkyl halide to form a phosphonate.
The Michaelis–Arbuzov reaction





The reaction was discovered by August Michaelis in 1898, and greatly explored by Aleksandr Arbuzov soon thereafter. This reaction is widely used for the synthesis of various phosphonates, phosphinates, and phosphine oxides. Several reviews have been published.The reaction also occurs for coordinated phosphite ligands, as illustrated by the demethylation of {(C5H5)Co[(CH3O)3P]3}2+ to give {(C5H5)Co[(CH3O)2PO]3}−, which is called the Klaui ligand.

Mechanism of the Michaelis-Arbuzov Reaction

Reaction mechanism

The mechanism of the Michaelis–Arbuzov reaction




The Michaelis–Arbuzov reaction is initiated with the SN2 reaction of the nucleophilic phosphite (1) with the electrophilic alkyl halide (2) to give a phosphonium intermediate (3). Triaryl phosphites, which are unable to perform the second step of the Michaelis–Arbuzov reaction, have been shown to produce stable phosphonium salts.[6] Likewise, aryl and vinyl halides are less reactive towards phosphites.
The displaced halide anion reacts via another SN2 reaction with the phosphonium intermediate to give the desired phosphonate (4) and another alkyl halide (5). When chiral phosphonium intermediates are produced, it has been shown the halide substitution proceeds with inversion of configuration, as expected by a SN2 reaction.[7]
As a general guideline, the reactivity of the organic halide (2) can be listed as follows: (from most reactive to least reactive)
and
The reaction of α-bromo- and α-chloroketones with phosphites yields a vinyl phosphate instead of an alkyl phosphonate – the Perkow reaction. α-Iodoketones do, in fact, give the a phosphonate.[8] Other methods of producing β-ketophosphonates have been developed.

Recent Literature


Lewis Acid-Mediated Michaelis-Arbuzov Reaction at Room Temperature: A Facile Preparation of Arylmethyl/Heteroarylmethyl Phosphonates
G. G. Rajeshwaran, M. Nandakumar, R. Sureshbabu, A. K. Mohanakrishnan, Org. Lett., 2011, 13, 1270-1273.

Generation of Phosphoranes Derived from Phosphites. A New Class of Phosphorus Ylides Leading to High E Selectivity with Semi-stabilizing Groups in Wittig Olefinations
V. K. Aggarwal, J. R. Fulton, C. G. Sheldon, J. de Vicente, J. Am. Chem. Soc., 2003, 125, 6034-6035.


Reliable and Versatile Synthesis of 2-Aryl-Substituted Cinnamic Acid Esters
A. Ianni, S. R. Waldvogel, Synthesis, 2006, 2103-2112.

Want other example click the link
http://www.google.co.in/patents/US3483279

Comments

Post a Comment

Popular posts from this blog

Reaction Procedure of Appel Reaction & Workup

Image
Org. Synth.   1974 ,  54 , 63 DOI: 10.15227/orgsyn.054.0063 Example 1:- GERANYL CHLORIDE [ 2,6-Octadiene, 1-chloro-3,7-dimethyl-,  (E) - ] Submitted by Jose G. Calzada and John Hooz 1 . Checked by K.-K. Chan, A. Specian, and A. Brossi. 1. Procedure A dry,  300-ml., three-necked flask  is equipped with a  magnetic stirring bar  and  reflux condenser  (to which is attached a  Drierite-filled drying tube ) and charged with  90 ml. of  carbon tetrachloride   (Note 1)  and  15.42 g. of  geraniol (0.1001 mole)   (Note 2) . To this solution is added  34.09 g. (0.1301 mole) of  triphenylphosphine   (Note 3) , and the stirred reaction mixture is heated under reflux for 1 hour. This mixture is allowed to cool to room temperature; dry  pentane  is added (100 ml.) , and stirring is continued for an additional 5 minutes. The  triphenylphosphine oxide ...
Read more

Acetoacetic-Ester Condensation Claisen Condensation

Image
The  Claisen condensation  is a carbon–carbon bond forming reaction that occurs between two esters or one ester and another carbonyl compound in the presence of a strong base, resulting in a β-keto ester or a β-diketone. It is named after Rainer Ludwig Claisen, who first published his work on the reaction in 1887. Requirements At least one of the reagents must be enolizable (have an α-proton and be able to undergo deprotonation to form the enolate anion). There are a number of different combinations of enolizable and nonenolizable carbonyl compounds that form a few different types of Claisen condensations. The base used must not interfere with the reaction by undergoing nucleophilic substitution or addition with a carbonyl carbon. For this reason, the conjugate sodium alkoxide base of the alcohol formed (e.g. s...
Read more

Aldol reaction

Image
The  aldol reaction  is a means of forming  carbon–carbon bonds  in  organic chemistry .T he reaction combines two  carbonyl  compounds (the original experiments used  aldehydes ) to form a new β-hydroxy carbonyl compound. These products are known as  aldols , from the  ald ehyde + alcoh ol , a structural motif seen in many of the products. Aldol structural units are found in many important molecules, whether naturally occurring or synthetic. For example, the aldol reaction has been used in the large-scale production of the commodity chemical  pentaerythritol  and the synthesis of the heart disease drug Lipitor ( atorvastatin , calcium salt). The aldol reaction unites two relatively simple  molecules  into a more complex one. Increased complexity arises because up to two new  stereogenic centers  (on the  α- and β-carbon  of the aldol adduct, marked with asterisks in the scheme below) are for...
Read more