Organic Reactions, Volume 2

CHAPTER 1
THE CLAISEN REARRANGEMENT
D. STANLEY TAEBBLL
The University of Rochester
CONTENTS
PAGE
INTRODUCTION 2
STRUCTURAL REQUIREMENTS FOR REARRANGEMENT; RELATED REARRANGE-
MENTS • 4
SCOPE AND LIMITATIONS . . . ./• 6
Rearrangement in Open-Chain Compounds 6
Rearrangement of Allyl Aryl Ethers 8
The ortho Rearrangement 8
The para Rearrangement 8
Effect of Substituents in the Allyl Group 9
Effect of Substituents in the Aromatic Nucleus 11
Displacement of Substituents 11
Relation of Bond Structure to Rearrangement 13
Side Reactions 14
Mechanism of the Rearrangement 16
Synthetic Application 17
OTHER METHODS OF SYNTHESIS OF ALLYLPHENOLS 20
EXPERIMENTAL CONDITIONS AND PROCEDURES 22
Preparation of Allyl Ethers 22
Conditions of Rearrangement 0 23
Experimental-Procedures 26
Allyl Phenyl Ether 26
Allyl 2,4-Dichlorophenyl Ether *. 26
2-Allylphenol 27
2-Methyldihydrobenzofuran „ 27
Isomerization of 2-Allylphenol to 2-Propenylphenol 27
C-Alkylation. Preparation of 2-Cinnamylphenol 28
EXAMPLES OF THE REARRANGEMENT 29
Table I. Rearrangement of Open-Chain Compounds 29
A. Ethers of Enols 29
B. Rearrangements' Involving Migration to an Unsaturated Side Chain . 29
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