Decarboxylations

Name Reactions

Recent Literature

A base-catalyzed Michael-type addition of sodium diethyl malonate to N-Boc-α-amidoalkyl-p-tolyl sulfones in tetrahydrofuran followed by hydrolysis of the adducts in refluxing 6 M aqueous hydrochloric acid affords β³-amino acid hydrochlorides in high yield and excellent purity.
M. Nejman, A. Śliwińska, A. Zwierzak, Tetrahedron, 2005, 61, 8536-8541.

An effective protocol allows the smooth protodecarboxylation of diversely functionalized aromatic carboxylic acids within 5-15 min under microwave irradiation. In the presence of an inexpensive catalyst generated in situ from copper(I) oxide and 1,10-phenanthroline, even nonactivated benzoates were converted in high yields.
L. J. Goossen, F. Manjolinho, B. A. Khan, N. Rodríguez, J. Org. Chem., 2009, 74, 2620-2623.

A simple and highly efficient protodecarboxylation of various heteroaromatic carboxylic acids is catalyzed by Ag₂CO₃ and AcOH in DMSO. This methodology enables also a selective monoprotodecarboxylation of several aromatic dicarboxylic acids.
P. Lu, C. Sanchez, J. Cornella, I. Larrosa, Org. Lett., 2009, 11, 5710-5713.

Diethyl N-Boc-iminomalonate, prepared on multi-gram scale, served as a stable and highly reactive electrophilic glycine equivalent which reacted with organomagnesium compounds affording substituted aryl N-Boc-aminomalonates. Subsequent hydrolysis produced arylglycines.
P. Cali, M. Begtrup, Synthesis, 2002, 63-64.

Enolizable carboxylic acids were converted in a single step to trifluoromethyl ketones. Treatment of the acid with LDA generated an enediolate that was trifluoroacetylated with EtO₂CCF₃. Quenching the reaction mixture with aqueous HCl resulted in rapid decarboxylation and provided the trifluoromethyl ketone product in good yield.
J. T. Reeves, J. J. Song, Z. Tan, H. Lee, N. K Yee, C. H. Senanayake, J. Org. Chem., 2008, 73, 9476-9478.

Malonic acid derivatives undergo unusually mild decarboxylation in the presence of N,N′-carbonyldiimidazole (CDI) at room temperature to generate a carbonyl imidazole intermediate in high yield. Subsequent reactions with various nucleophiles in an efficient one-pot process leads to amides, esters or carboxylic acids.
D. Lafrance, P. Bowles, K. Leeman, R. Rafka, Org. Lett., 2011, 13, 2322-2325.

A straightforward route allows the synthesis of 2-(hetero)arylated and 2,5-di(hetero)arylated oxazoles through regiocontrolled palladium-catalyzed direct (hetero)arylation of ethyl oxazole-4-carboxylate with iodo-, bromo-, and chloro(hetero)aromatics.
C. Verrier, T. Martin, C. Hoarau, F. Marsais, J. Org. Chem., 2008, 73, 7383-7386.

A Novel Approach to 1-Monosubstituted 1,2,3-Triazoles by a Click Cycloaddition/Decarboxylation Process
M. Xu, C. Kuang, Z. Wang, Q. Yang, Y. Jiang, Synthesis, 2011, 223-228.

Related

A novel electrolytic system for non-Kolbe electrolysis based on the acid-base reaction between carboxylic acids and solid-supported bases in MeOH provide the corresponding methoxylated products in excellent yields. The acid-base reaction between carboxylic acids and solid-supported bases preferentially takes place to reduce the cell voltage in MeOH.
T. Tajima, H. Kurihara, T. Fuchigami, J. Am. Chem. Soc., 2007, 129, 6680-6681.

A highly enantioselective, general catalytic system for the facile synthesis of tertiary stereocenters adjacent to cyclic ketones relies on catalytic decarboxylative protonation of readily accessible racemic quaternary β-ketoesters.
J. T. Mohr, T. Nishimata, D. C. Behenna, B. M. Stoltz, J. Am. Chem. Soc., 2006, 128, 11348-11349.

Mild and selective heterobimetallic-catalyzed decarboxylative aldol reactions of allyl β-keto esters with aldehydes are promoted by Pd(0)- and Yb(III)-DIOP complexes at room temperature. The optimized reaction conditions require the addition of both metals.
S. Lou, J. A. Westbrook, S. E. Schaus, J. Am. Chem. Soc., 2004, 126, 11440-11441.

In the presence of as little as one mol-% of a Lewis acid catalyst, e.g. Mg(ClO₄)₂ or Cu(OTf)₂, carboxylic acids can easily and near quantitatively be protected in a decarboxylative esterification at room temperature as methyl, benzyl, or t-butyl esters.
L. Goossen, A. Döhring, Adv. Synth. Catal., 2005, 345, 943-947.

A hypervalent iodine reagent, (diacetoxyiodo)benzene, and catalytic amount of sodium azide in acetonitrile enable an oxidative decarboxylation of 2-aryl carboxylic acids into the corresponding aldehydes, ketones, and nitriles in good yields at room temperature. The advantages of this protocol are short reaction times and mild reaction conditions.
V. N. Telvekar, K. A. Sasane, Synlett, 2010, 2778-2779.