Synthetic application of pipecolic acid Seetaram Mohapatra • Sujitlal Bhakta • Nilofar Baral • Sabita Nayak Received: 4 October 2013 / Accepted: 29 January 2014 / Published online: 21 February 2014 Ó Springer Science+Business Media Dordrecht 2014 Abstract Pipecolic acid is used as organocatalyst and novel substrate in organic synthesis. Organocatalysis-based methodologies for asymmetric transformations are now the frontier field of research in chiral synthesis. In the recent years, pipecolic acid opens a new avenue as an organocatalyst and as an important substrate in various reactions. This review summarized the most significant advances of pipecolic acid reported in the literature from 2000 to 2013. Keywords Asymmetric synthesis Á Organocatalysis Á Pipecolic acid Á Cycloaddition Á Nitrochromene Á Spirooxindole Á Asymmetric catalyst Introduction Organic transformations promoted by small organic molecules, called organocatal- ysis [1–3], have emerged as a new and powerful synthetic paradigm in organic synthesis. Because of ready availability, operational simplicity, eco-friendliness, and low toxicity associated with the organocatalysis, they are now complementary to well-established biocatalysis and organometallic catalysis. In this scenario, cyclic a- amino acids such as L-proline and its derivatives find many applications in organic synthesis such as small molecule organocatalysts [4–6]. The presence of a secondary amino group and a carboxylic acid moiety in its structure functioning as a bronsted acid efficiently catalysed the reactions. L-proline and its derivatives, promoting aldol, [7] Mannich, [8, 9] Michael, [10, 11] Diels–Alder [12, 13], a-amination, and Knoevenagel-type reactions [12, 13], are well documented in literature. Recently, pipecolic acid (piperidine-2-carboxylic acid) [14, 15] (Fig. 1), the higher analogue of proline and the derived catalysts, have served as organocatalytic probes and valuable S. Mohapatra (&) Á S. Bhakta Á N. Baral Á S. Nayak Department of Chemistry, Ravenshaw University, Cuttack 753 003, Odisha, India e-mail: seetaram.mohapatra@gmail.com 123 Res Chem Intermed (2015) 41:4545–4553 DOI 10.1007/s11164-014-1550-8