Synthesis of new siloxane or sulfur containing symmetrical monomers based on carvone

Abstract

We demonstrated, that based on carvone, new symmetrical AA-type monomers with double bonds can be easily prepared by thiol-ene or Michael addition of dithiols. Moreover, hydrosilylation reaction with difunctional telehelic siloxane, containing Si-H groups was also studied. Obtained monomers are suitable for further polymerization by thiol-ene or hydrosilylation polyaddition.

GRAPHICAL ABSTRACT

Keywords:

• Carvone
• hydrosilylation
• thiol-ene
• click
• Michael addition

Acknowledgment

NMR analysis and investigation of molecular-weight characteristics of polymer was made using the equipment of the Collaborative Access Center “Center for Polymer Research” of ISPM RAS.

Disclosure statement

No potential conflict of interest was reported by the authors.

Scheme 1 depicts the synthesis of different dithiol (1, 2) and siloxane (3) derivatives of carvone. First, we performed Michael-type thiol addition to conjugated cyclohexene double bound in standard conditions.^[9] It should be noted, that the product 1 was isolated during the reaction as a separate phase, which can be easily removed and purified simply by rinsing with pure methanol. This compound is remarkable due to content of symmetric functional double bonds and ketogroups. These functional groups can be used for further polymerization and functionalization.

Notes

1 Hexamethylenetrisiloxane (HMTS) was synthesized according to the procedure described in Russ. J. Gen. Chem., 2003, 73, 157.

Additional information

Funding

This work was supported by the Russian Foundation for Basic Research (grant no. 19-29-05227 МК).