Method for preparing silicon-containing heterocycles

A method for preparing a silicon-containing heterocycle of the general formula (I)

• wherein R1 is hydrogen;
• R2 and R3 are same or different and are, independently from one another, selected from a linear or branched, substituted or unsubstituted C1-C20 alkyl or C6-C18 aryl residue which may be interrupted by at least one heteroatom;
• R4 is selected from a linear or branched, substituted or unsubstituted C1-C20 alkylene residue which may be interrupted by at least one heteroatom;
• R5 and R6 are same or different and are, independently from one another, selected from the group consisting of hydrogen, a linear or branched, substituted or unsubstituted C1-C20 alkyl or C6-C18 aryl which may be interrupted by at least one heteroatom, and a C4-C8 cycloalkyl, or R5 and R6 may form a ring, a 4- to 8-membered alkyl ring;
• and
• n is 0, 1 or 2,
• said method comprising:
• providing at least one epoxide compound of the general formula (II)
• wherein R5 and R6 are the same as defined for the general formula (I) above;
• providing at least one aminoalkoxysilane having a primary amino group;
• providing a catalyst, wherein the catalyst comprises a Lewis acid selected from the group consisting of calcium bistrifluoroacetate, calcium bisacetate, calcium bispivalate, calcium bisisobutyrane, calcium bispropionate, calcium acetate, calcium benzoate, calcium cyclohexanecarboxylate, calcium 2,2-difluoroacetate, calcium 2-fluoroacetate, calcium 2-chloroacetate, calcium methyl carbonate, magnesium bistrifluoroacetate, magnesium bisacetate, magnesium bispivalate, magnesium bisisobutyrane, magnesium bispropionate, magnesium acetate, magnesium benzoate, magnesium cyclohexanecarboxylate, magnesium 2,2-difluoroacetate, magnesium 2-fluoroacetate, magnesium 2-chloroacetate, and magnesium methyl carbonate;
• combining the at least one epoxide compound, the at least one aminoalkoxysilane and the catalyst to form a mixture;
• and
• exposing the mixture to conditions suitable to react the at least one epoxide compound with the at least one aminoalkoxysilane in the presence of the catalyst to form the silicon-containing heterocycle of general formula (I).