Reactions of glycidyl derivatives with ambident nucleophiles; part 2: amino acid derivatives

• Gerald Dyker,
• Andreas Thöne and
• Gerald Henkel

Beilstein J. Org. Chem. 2007, 3, No. 28, doi:10.1186/1860-5397-3-28

• multifunctionalized heterocycles from a pyroglutamic acid derivative, glycidyl components and anilines by nucleophilic substitution and cobalt catalysis is presented. Introduction Recently we investigated the formation of 5- and 6-membered heterocycles from ethyl acetoacetate and glycidyl derivatives such as

• ) no cyclization products were obtained. Finally we succeeded in achieving a cyclization by a two-step procedure: the cobalt-catalyzed addition of electron-rich anilines 6 according to Iqbal [9] let to amino alcohols 7, which then cyclized in basic medium (NaH in DMF or THF), either to give 7-membered

• achieved the annulation reaction of amino acid derivatives with glycidyl compounds as functionalized C3 building blocks in combination with a cobalt-catalyzed addition of anilines to the epoxide functionality. This rather selective transition-metal catalysed step builds up the alcohol and the amino

The use of silicon- based tethers for the Pauson- Khand reaction

• Adrian P. Dobbs,
• Ian J. Miller and
• Saša Martinović

Beilstein J. Org. Chem. 2007, 3, No. 21, doi:10.1186/1860-5397-3-21

• consistent with the literature evidence and our previous results that the 5,7 systems are known not to be synthesised through the cobalt mediated methodology. The unsymmetrical acetal was recovered in near quantitative yield with no trace of any products of decomposition or hydrolysis. Therefore silyl acetal

Cobalt(II) chloride catalyzed one-pot synthesis of α-aminonitriles

• Surya K. De

Beilstein J. Org. Chem. 2005, 1, No. 8, doi:10.1186/1860-5397-1-8

• synthesis of α-aminonitriles. In continuation of our work to develop new organic transformations, [11][12][13][14][15][16][17] I report herein that cobalt(II) chloride which acts as a mild Lewis acid might be a useful and inexpensive catalyst for the synthesis α-aminonitrile. Although cobalt(II) chloride

• has been extensively used as a mild catalyst for a plethora of organic transformations, [18][19][20] there are no examples of the use of cobalt(II) chloride as catalyst for the synthesis of α-aminonitriles. Results and discussion The treatment of benzaldehyde and aniline with KCN in the presence of a

• , efficient, and practical method for the synthesis of α-aminonitriles through a one-pot three component coupling of aldehydes, amines, and potassium cyanide using a catalytic amount of cobalt(II) chloride. The major feature of this method is that it is truly a one-pot protocol that does not need a separate