Dynamic property name in a collection

Hi i have json list returned from REST as follows,

{
list: [2]
{
"0": {
"name": "P06"
"_id": "abc123"
"_rev": "4231"
},
"1": {
"name": "P07"
"_id": "xyz123"
"_rev": "1578"
}
}
}

Instead of above structure in need the json to be as following, ie. index number must be a value of property, here it is "name"

{
list: [2]
{
"P06": {
"name": "P06"
"_id": "abc123"
"_rev": "4231"
},
"P07": {
"name": "P07"
"_id": "xyz123"
"_rev": "1578"
}
}
}

My class structre as follows ...

public class MainModel
{
public List<LookUpModel> list { get; set; }
}

public class LookUpModel
{
public string _id { get; set; }

public string _rev { get; set; }

public string name { get; set; }
}

Thanks,