# 0.2 Grignard reaction  (Page 2/5)

 Page 2 / 5

This $\delta -$ carbon consequently has significant nucleophilic character. The Grignard reagent reacts well as a nucleophile with the $\delta +$ -carbon of the carbonyl group as a target. The C=O π-bond is broken and the carbonyl becomes an alcohol. In the process, a new carbon-carbon bond is formed between the Grignard reagent and the carbonyl carbon - now the alcohol carbon.

The intermediate alkoxymagnesium salt is neutralized by acid in the work-up to produce the alcohol product. Before we go on to look at more Grignard reactions with carbonyl groups, here is a problem for you to try.

• Identify the product (A-E) (5 points)

GR adds to a carbonyl compounds to generate alcohols. A more modern interpretation extends the scope of the reaction to include the addition of Grignard reagents to a wide variety of electrophilic substrates:

Depending upon the amount of GR used and the substrate, it can give different types of products after working up the reaction. Here is an example:

Addition of GR to α, β unsaturated carbonyls:

GR adds to carbonyl center mainly in two fashions. Alkyl lithium halides add only in 1, 2-fashion because R-Li is a more reactive organometallic compound than others, so it prefers to add to most HARD carbonyl carbon center (since it is more electrophilic in nature). On the other hand, ${R}_{2}\text{CuLi}$ or $R-\text{MgX}/{\text{Cu}}^{2+}$ adds only in 1,4- fashion, because C-4 is soft towards electrophilicity and soft cuprate reagents prefer to add only to soft centers according to HSAB (Hard Soft Acid Base ) theory. Traditional GR (alkyl magnesium halide) is intermediate in its’ reactivity, so a mixture of 1, 2- and 1, 4- addition product is obtained. Here is an example of a GR adding to a α, β unsaturated carbonyl compound:

Most alcohols can be produced by a Grignard reaction. In deciding how to do this carry out the reaction, think about the Grignard reaction in reverse: if your target alcohol had been the result of a Grignard reaction, what would the carbonyl compound have to be? What would the Grignard reagent have to be?

Consider the scheme below for the synthesis of 1-phenyl-1-butanol via a Grignard reaction. Two different ways to synthesize this compound are shown. Can you think of a third?

## Important facts:

Grignard reagent (RMgX) is a very polar reagent and a very strong Lewis base and therefore will be easily protonated by water, which acts as a strong acid when in contact with a Grignard reagent. The reagent’s reaction with water produces a gelatinous metal hydroxide. Since it reacts rapidly with the acidic hydrogen atom, the reaction must be carried out under dry conditions since even a small amount of moisture can destroy the reagent. The reactivity of Grignard reagent depends on mainly two factors:

1. Types of metal center (Li>K>Mg etc)

2. Types of halides present (I>Br>Cl) and

3. Types of solvent used.

In presence of different functional groups, the order of reactivity of GR is as follows:

## Our experiment:

In this experiment, the addition of a nucleophilic Grignard reagent (1-methylbutylmagnesium bromide), to the electrophilic carbonyl carbon of an aldehyde (propanal) is performed.

can someone help me with some logarithmic and exponential equations.
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
Commplementary angles
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
a perfect square v²+2v+_
kkk nice
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
rolling four fair dice and getting an even number an all four dice
Kristine 2*2*2=8
Differences Between Laspeyres and Paasche Indices
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
is it 3×y ?
J, combine like terms 7x-4y
im not good at math so would this help me
yes
Asali
I'm not good at math so would you help me
Samantha
what is the problem that i will help you to self with?
Asali
how do you translate this in Algebraic Expressions
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
what's the easiest and fastest way to the synthesize AgNP?
China
Cied
types of nano material
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
what is nanomaterials​ and their applications of sensors.
what is nano technology
what is system testing?
preparation of nanomaterial
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
what is system testing
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
can nanotechnology change the direction of the face of the world
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
how did you get the value of 2000N.What calculations are needed to arrive at it
Privacy Information Security Software Version 1.1a
Good
Got questions? Join the online conversation and get instant answers!