Alkyl and Aromatic Esters

A new material for the microencapsulation of biological systems was discovered and characterized with regards to the effects of reaction conditions on product yield. By using poly(cyanoacrylate ester), membrane microcapsules were produced with sufficient strength and porosity to be effective in a process environment for the immobilization and protection of encapsulated material. After synthesizing numerous monomeric cyanoacrylate esters, the n-butyl derivative was discovered to give the best results with regards to microcapsule formation.

An alpha-cyanoacrylate may be formed by first condensing a cyanoacetate with paraformaldehyde or formaldehyde; reacting the polymer formed with an alcohol to transesterify the polymer; and depolymerizing the polymer to form alpha-cyanoacrylate monomers.

A study was conducted to investigate the differences in reactivity between ethyl cyanoacrylate (ECA) with phosphines and amines, which contain different alkyl substituents. It was found that when an equimolar amount of dimethylphenylphosphine and ECA react, a stable zwitterion is formed. This is the first time the proposed initiating species for alkyl cyanoacrylate polymerization has been sufficiently stable to be isolated and fully characterized spectroscopically.

A process for the preparation of esters, including non-distillable esters, of 2-cyanoacrylic acid comprises reacting 2-cyanoacrylic acid or an acid halide thereof with an alcohol, including a diol or polyol, or a phenol in the presence of an inert organic solvent under polymerisation inhibiting conditions and, additionally, in the presence of an acid catalyst when 2-cyanoacrylic acid is a reactant, continually removing the water or hydrohalic acid produced and recovering the ester.

The formulations comprise an alkyl C1-C8 cyanoacrylate and an alkyl C1-C8 carboxyacrylate in a proportion from 10 to 30 % by volume with respect to the cyanoacrylate. The alkyl carboxyacrylate of formula (I) is a new product which is obtained from the corresponding cyanoacrylate by hydrolysis with hydrochloric acid. The compositions are packaged in independent containers the content of which is mixed not more than one hour before its use. It can be used in surgery as alternative means for the traditional suture and is specially appropriate in ophthalmics surgery.

A monomer composition comprising at least one polymerizable alkyl ester α-cyanoacrylate monomer.

Alkyl propiolate couples with itself in the presence of catalytic DABCO under very mild conditions to provide a quantitative yield of E-hex-2-en-4-yne dioates. Hydrogenation of these enyne dioates using Lindlar catalyst provides the corresponding E,Z-diene dioate, a common structural motif found in an array of natural products.