Carroll rearrangement

Palladium-catalyzed processes

With palladium(0) as a catalyst, the reaction (Tsuji, 1980) is much milder (path B) with an intermediate allyl cation / carboxylate organometallic complex.

Decarboxylation precedes allylation as evidenced by this reaction catalyzed by tetrakis(triphenylphosphine)palladium(0):

Asymmetric decarboxylative allylation

By introducing suitable chiral ligands, the reaction becomes enantioselective.

The first reported asymmetric rearrangement is catalyzed by tris(dibenzylideneacetone)dipalladium(0) and the Trost ligand:

A similar reaction uses additional naphthol.

This reaction delivers the main enantiomer with 88% enantiomeric excess. It remains to be seen if this reaction will have a wide scope because the acetamido group appears to be a prerequisite.

The same catalyst but a different ligand is employed in this enantioconvergent reaction:

The scope is extended to asymmetric α-alkylation of ketones masked as their enol carbonate esters:Palladium-Catalyzed Asymmetric Allylic α-Alkylation of Acyclic Ketones Barry M. Trost and Jiayi Xu J. Am. Chem. Soc.; 2005; 127(49) pp 17180 - 17181; (Communication)

References

References

1. Carroll, M. F. "131. Addition of α,β-unsaturated alcohols to the active methylene group. Part I. The action of ethyl acetoacetate on linalool and geraniol". ''[[Journal of the Chemical Society]]'' '''1940''', 704–706. {{doi. 10.1039/JR9400000704
2. Charles S. Sell. (2013). "Kirk-Othmer Chemical Technology of Cosmetics". John Wiley & Sons.
3. ''Palladium-catalyzed rearrangement of allylic esters of acetoacetic acid to give γ,δ-unsaturated methyl ketones'' [[Tetrahedron Letters]], Volume 21, Issue 33, '''1980''', Pages 3199-3202 Isao Shimizu, Toshiro Yamada and [[Jiro Tsuji]] {{doi. 10.1016/S0040-4039(00)77444-2
4. ''Enantioselective Palladium-Catalyzed Decarboxylative Allylic Alkylations'' Shu-Li You and Li-Xin Dai [[Angew. Chem. Int. Ed.]] '''2006''', 45, 5246 – 5248 {{doi. 10.1002/anie.200601889
5. ''Asymmetric Allylic Alkylation of Ketone Enolates: An Asymmetric Claisen Surrogate'' Erin C. Burger and Jon A. Tunge [[Org. Lett.]]; '''2004'''; 6(22) pp 4113 - 4115; (Letter) {{doi. 10.1021/ol048149t
6. Kuwano, R.; Ishida N.; Murakami, M. "Asymmetric Carroll rearrangement of allyl α-acetamido-β-ketocarboxylates catalysed by a chiral palladium complex". ''[[Chemical Communications]]'' '''2005''', (31), 3951–3952. {{doi. 10.1039/b505105c
7. ''Deracemization of Quaternary Stereocenters by Pd-Catalyzed Enantioconvergent Decarboxylative Allylation of Racemic b-Ketoesters'' Justin T. Mohr, Douglas C. Behenna, Andrew M. Harned, and Brian M. Stoltz Angew. Chem. Int. Ed. '''2005''', 44, 6924 –6927 {{doi. 10.1002/anie.200502018