use tempdb;
GO 

CREATE TABLE #Table1
  (
  [Id] int NOT NULL PRIMARY KEY,
  [DaOr] datetime NOT NULL
  )  ON [PRIMARY]

INSERT #Table1 ([Id], [DaOr]) VALUES 
(1, N'2015-02-02T13:05:00'),
(2, N'2015-02-02T11:10:00'),
(3, N'2015-02-02T12:00:00'),
(9, N'2015-12-10T15:32:00'),
(10, N'2015-12-10T15:00:00'),
(11, N'2015-12-10T16:52:00'),
(12, N'2015-12-12T23:00:30'),
(13, N'2015-06-04T22:00:00'),
(14, N'2015-02-02T10:40:40'),
(15, N'2015-01-02T14:00:08'),
(16, N'2015-02-02T10:00:00');
GO

SELECT
    id
  , HourDate = CAST(CONVERT(char(17), DaOr, 113) as datetime)
  , progressivo = ROW_NUMBER() OVER(ORDER BY DaOr)
  INTO #TempHourDates
FROM
  #Table1;

WITH CTE AS 
(
    SELECT
      T1.Id
      , KeepOrDelete = CASE WHEN DATEDIFF(MINUTE, T1.HourDate, T2.HourDate) > 60 THEN 'KEEP' WHEN T2.HourDate IS NULL THEN 'KEEP' ELSE 'DEL' END
    FROM
      #TempHourDates T1
      LEFT JOIN #TempHourDates T2 ON T1.progressivo + 1 = T2.progressivo
)

DELETE FROM #Table1
WHERE Id IN 
(
  SELECT Id FROM CTE WHERE CTE.KeepOrDelete = 'DEL'
);


SELECT * FROM #Table1;

DROP TABLE #Table1;
GO
DROP TABLE #TempHourDates;
GO