Chapter 11: Q58P (page 590)
The following pseudo-syntheses (guaranteed not to work) exemplify a common conceptual error.
(a)What is the conceptual error implicit in these syntheses?
(b)Propose syntheses that are more likely to succeed.
Short Answer
(a) The misconception in the reactions is that the first reaction has incompatible reagents or conditions. The first reaction will lead to a neutralization reaction.
(b)
Step by step solution
About organic synthesis
The branch of chemistry deals with the synthesizing of organic compounds using some simple molecules called starting materials.
Starting materials are commercially available, and the molecule is simple. The simpler the molecule, the easier will be the mechanism of the reaction.
Abut the given reaction
In this reaction, a bromoalkane is subjected to heat followed by treatment with salt. It results in the formation of methoxy alkane.
The second reaction is the treatment of an alcohol with an acid that results in the formation of a methoxy group attached to alkane.
Conceptual error in the given reaction
The two reactions show that the incompatible conditions or reagents can coexist. For the first reaction, SN1 conditions are not compatible withSN2 conditions with sodium methoxide.
The tertiary carbocation in the first step will not remain until sodium methoxide addition in the second step. This is a conceptual error.
Conceptual error in the given reaction
The second reaction shows the acidic condition in the first step, which is incompatible with the basic condition in the second step. If it is a basic sodium methoxide, it undergoes a neutralization reaction by giving methanol.
This is the conceptual error in the second reaction. So, there is no reaction.
Syntheses that are more likely to succeed
The possible synthesis is given below.
The possible syntheses are given below.
Over 30 million students worldwide already upgrade their learning with Vaia!
