The Brook rearrangement, discovered by Adrian Gibbs in 1958, involves the 1,2-migration of a silyl group from carbon to oxygen under basic conditions, resulting in an intramolecular rearrangement. The reaction, which exhibits pseudofirst order kinetics and can involve different elements such as nitrogen and sulfur, has various synthetic applications, including the synthesis of complex organic compounds. The document outlines key characteristics, mechanisms, and methods for generating α-silylalkoxides related to this reaction.

1. BROOK
REARRANGEMENT
PREPARED BY
ANUSREE V
1ST SEMESTER MPHARM
PHARMACEUTICAL CHEMISTRY
AL SHIFA COLLEGE OF PHARMACY

2. INTRODUCTION
Discovered by Canadian Chemist
Adrian Gibbs Brook in 1958.
Also known as [1,2]-Brook
rearrangement or [1,2]-Silyl
migration.
Intramolecular rearrangement.
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3. DEFINITION
 The 1,2- migration of a silyl group from carbon
to oxygen under basic conditions is known as
Brook rearrangement.
 Rearrangement of α-silyloxyanion to α-
silylcarbanions involving a pentacoordinate
siliconintermediate. 3

4. 4
Alpha-silyl
oxyanion
Pentacoordinate
siliconintermediate
Alpha-silyl
carbanion
Silyl ether or
Oxysilane

5. REACTION
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6. METHODS FOR GENERATION OF
α -SILYLALKOXIDES
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7. MECHANISM
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8. CHARACTERISTICS
 The rate of reaction depends on the amount of
added base, but this was not consumed and was
used in substoichiometric amounts. So the
reaction follows Pseudofirst order kinetics.
 A silyl shift from oxygen to carbon, the reverse
process is called retro-Brook rearrangement. 8

9. •[1,2]-silyl migration is a equilibrium process.
•Aza- or Thia- variants of the rearrangement
involving silyl shifts from carbon to nitrogen or
sulphur respectively, have also been observed.
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10. SYNTHETIC APPLICATIONS
 K. Takeda and co-workers synthesized the tricyclic core
of the cyanthins using a Brook rearragement mediated-
reaction.
APPLICATION 1:
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11. APPLICATION 2:
 K. Takeda developed a new synthetic strategy for the
stereoselective construction of 8 membered
carbocycles utilizing a Brook rearrangement.
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12. APPLICATION 3:
 E.J. Corey synthesized (+)- Onocerin from farnesyl
acetate- derived acyl silane via four-component
coupling and tetracyclization steps.
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13. REFERENCE
 JiebJack Li:Name Reactions Third Edition;Springer
Science & Bussiness Media, 2006:Page no:83-84
 Laszlo Kurti,Barbara Czako:Strategic Applications of
Named Reactions in Organic Synthesis;Elsevier,29-
Apr-2005;page no:64-65
 Christian M. Rojas:Molecular Rearrangements in
Organic Synthesis:Wiley,March-2015,Page no:207-241
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14. 14
A. Hassner, I.Namboothiri;Organic Syntheses Based
on Named Reactions, Third Edition;Elsevier;Page no:62
Michiko Sasaki, Kei Takeda:Brook rearrangement:
Wiley Online library:2-Oct-2015:Chapter 6
TutorVista.com

15. THANK YOU...
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