Synthesis
GENERAL STEPS: 2-Methylbenzaldehyde (50 g, 417 mmol) was dissolved in pyridine (2 eq., 65 mL) under stirring conditions, followed by the addition of malonic acid (86.6 g, 834 mmol). The reaction mixture was heated to reflux for 4-5 hours. Upon completion of the reaction, the mixture was slowly poured into ice water and then acidified with 1N HCl. The precipitated white solid was collected by filtration, washed with water and dried under high vacuum for 3-4 h to give (E)-3-(o-tolyl)acrylic acid (57 g, 87% yield).
References
[1] Patent: US2013/178457, 2013, A1. Location in patent: Paragraph 0173
[2] Patent: WO2013/5168, 2013, A2. Location in patent: Page/Page column 32
[3] Tetrahedron Letters, 2011, vol. 52, # 41, p. 5371 - 5374
[4] Journal of Organic Chemistry, 1986, vol. 51, # 7, p. 1120 - 1123
[5] Patent: WO2013/74892, 2013, A1. Location in patent: Page/Page column 39-40
