The Addition of Saturated Heterocyclic Amines to Cinnamate Esters

Abstract

Saturated Heterocyclic Amines and Cinnamate Esters 4089 Isodextropimaric Acid.-The previously described chromium trioxide oxidation procedure was used without modification to oxidize 1.40 g. of the isodextropimarinal-containing carbonyls isolated above. The resulting acids were isolated by basic extraction from ether solution as before. Evaporation of the ether solution yielded 0.65 g. of unoxidized carbonyl compounds which gave a positive test with 2,4-dinitrophenylhydrazine and a negative Tollens test. A very small quantity of white crystals which precipitated from the dilute alkaline solution was presumed to be sodium dextropimarate and discarded. Acidification of the alkaline solution with 2 M acetic acid followed by heptane extraction, removal of excess acetic acid by several water washings, and treatment of the heptane solution with 2-amino-2-methyl-l-propanol yielded 0.20 g. of the amine salt, [a]24D -11.2°. Successive recrystallizations of the salt from acetone solution served to increase the negative rotation to -14.4°. The amine salt showed very low absorption in the ultraviolet, indicative of only minor amounts of contaminants: general absorption 235-275 µ, Xmax 248-256 µ (a 2.0). Conversion of the salt to the cyclohexylamine salt followed by recrystallization from acetone showed similar results. However, the cyclohexylamine salt of isodextropimaric acid was found to be concentrated in the mother liquors. Treatment of the cyclohexylamine salt, [a]26D ±0°, with acetic acid yielded isodextropimaric acid, m.p. 161-163.5°.

Chemoselective Synthesis of Substituted Imines, Secondary Amines, and β‐Amino Carbonyl Compounds from Nitroaromatics through Cascade Reactions on Gold Catalysts

“…One-pot synthesis of substituted b-amino carbonyl compounds from nitroaromatics and a,b-unsaturated ketones with a bifunctional catalyst: For several decades, the Michael addition reaction between amines and a,b-unsaturated ketones (see the example in Scheme 5) has been used as an important tool for preparative organic synthesis. The obtained b-amino carbonyl functionalities are ubiquitous motifs in natural products such as alkaloids and polyketides, [40][41][42][43] as well as important intermediates for the synthesis of amino alcohols, diamines, and b-amino acid derivatives or b-lactams, [44][45][46][47][48][49][50][51] many of which are used, among other pharmaceutical applications, as powerful antibiotics. Michael reactions are facilitated by protic acid, protic base, or Lewis acid catalysts [40,48,[52][53][54][55][56][57] and can proceed through Markovnikov or anti-Markovnikov additions, which lead to either branched or linear compounds, respectively.…”

Heat Capacity, Density, Vapor Pressure, and Enthalpy of Vaporization of Propyl Cinnamate

“…In addition, they were also reported as antimicrobial agents. 13,14 Unfortunately, only limited data for the vapor pressure 15,16 and density 15,17 of propyl cinnamate are available. In addition, other thermodynamic properties such as heat capacity and enthalpy of vaporization of propyl cinnamate were not mentioned in the literature studies.…”

“…Cinnamic acid and its esters are often used as synthetic raw materials for plant growth regulators and expected to be alternatives for synthetic pesticides because of their repellent or insecticidal activity. In addition, they were also reported as antimicrobial agents. , Unfortunately, only limited data for the vapor pressure , and density , of propyl cinnamate are available. In addition, other thermodynamic properties such as heat capacity and enthalpy of vaporization of propyl cinnamate were not mentioned in the literature studies.…”

Ordered organo-inorganic hybrid mesoporous solid acid catalysts (Zr–TMS–TFA) for Michael addition of indoles with α,β-unsaturated carbonyl compounds under environmentally benign solvent free conditions

“…Also, nitrogen-containing compounds are of significant importance in biologically active substances, dyes, and fine chemicals [6,7]. Further, the b-amino carbonyl group is a common moiety in a large variety of biologically active compounds such as alkaloids and polyketides [8][9][10][11]. They serve as attractive precursors in the preparation of c-amino alcohol, b-lactams, bamino acid derivatives and chiral auxiliaries [12][13][14][15][16], where many of which serve as antibiotics or other drugs [17][18][19].…”