Nested pseudoclasses in Less css

I am trying to use LESS CSS to write my CSS but i got a problem with nested pseudoclasses I

.class1 { 
        &:nth-of-type(2n) {  
            .class2{  
            } 
        } 
    }

the output is:

.class1.class2:nth-of-type(2n) {}

but I want to have this:

.class1:nth-of-type(2n) .class2{}

Any ideas?