Dynamic pivot query in sql

DECLARE @year AS NVARCHAR(MAX),

    @query  AS NVARCHAR(MAX)

select  @year= coalesce(@year+',['+cast((Year) as varchar(4))+']','['+cast(Year as varchar(4))+']')

from (select distinct  Year(OrderDate) year from [Sales].[SalesOrderHeader])t

set @query='

select Name,'+@year+' from (select p.Name,YEAR(OrderDate) year,LineTotal from  [Sales].[SalesOrderHeader] s

join [Sales].[SalesOrderDetail] o on s.SalesOrderID=o.SalesOrderID

join [Production].[Product] p on o.ProductID=p.ProductID) t

pivot

(

sum(LineTotal)

for year in ('+@year+')

) p1';

exec (@query)