Esters primary aminomethylation

The first amino substituted boronic esters were tertiary amines derived from dibutyl (iodomethyl)boronate and secondary amines [58]. Mysteriously, ammonia did not yield the simple (aminomethyl)boronic ester, but ilure of a reaction does not prove anything. Subsequent rechecking with primary, secondary, and tertiary amines as reactants showed that primary amines with dibutyl (iodomethyl)boronate did not yield isolable primary (aminomethyl)boronic esters [59]. The tertiary amines and quaternary ammonium salts derived from secondary and tertiary amines were stable and easily isolable. 

In an opposite manner to bases such as 1 and 2 in terms of reactivity, polymer-supported tosyl chloride equivalent 14 is able to capture alcohols as polymer-bound sulfonates 15, which are released as secondary amines, sulfides and alkylated imidazoles with primary amines, thiols and imidazoles as nucleophiles in a substitution process (Scheme 6) [24]. This technique has further been extended for the preparation of tertiary amines [25] and esters [26]. Excess of amine was scavenged by polymer-supported isocyanate 16 [27, 28] while excess of carboxylic acid was removed by treatment with aminomethylated polystyrene 17. 

The classical Mannich reaction converts phenols to aminomethylated phenols. The reaction involves the addition of phenols to C=N bonds of imines or iminium salts formed from formaldehyde and primary or secondary amines, respectively . Recent modifications employ the reaction of an aminal in the presence of SO3, which gives a sulfonate ester, followed by o-aminomethylation (equation Sc(OTf)3 catalyzed... 

Preparation of 30 and cleavage from the support to yield the primary amine The linker 29 (1.0 equiv.) and the primary amine (1.0 equiv, L-phenylalanine methyl ester) were reacted in DMF at rt to form the desired vinylogous amide. This vinylogous amide (2.5-fold excess relative to the loading of the support) was attached to aminomethyl polystyrene with TPTU as activating agent... 

Ethyl oleate was examined in non-isomerizing HAM with a variety of primary and secondary amines to produce mainly 9- or 10-aminomethyl-substituted stearic acid esters (Scheme 5.100) [87]. With the exception of diisopropylamine, almost excellent yields were achieved. When an excess of the fatty acid ester with regard to the amine (hexylamine) was used, two oleo compounds could be linked via an... 

In 2009, Theato and Jochum proposed a concept for modifying poly (pentafluorophenyl acrylate) (PPFPA) sequentially in a two-step reaction [11]. As shown in Scheme 5, the activated PFP-ester was treated with two different primary amines to first obtain a statistical copolymer. Using 4-(aminomethyl) aniline in this step enabled formation of an imide by adding 2-hydroxybenzaldehyde in a subsequent step. This approach facilitated the synthesis of doubly functionalized polymers from simple starting materials. Furthermore, the assignment of different amine ratios appeared to be an easy tool for adjusting the lower critical solution temperature (LCST) properties of the resulting polymers. 

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