Insert in to table without duplicate records TSQL
INSERT INTO table1 (ID, Name, pin)
SELECT table2.ID, table2.Name, table2.pin
FROM table2
LEFT JOIN table1 ON t1.Name=t2.Name
WHERE t1.Name IS NULL

or
INSERT INTO table1 (ID, Name, pin)
SELECT ID, Name, pin
FROM table2
WHERE NOT EXISTS ( SELECT NULL
                   FROM table1 
                   WHERE t1.Name=t2.Name )

If table1.ID value is an identity and must not be inserted but generated then replace ID in SELECT with NULL.