Boston College (7-19, 3-10 Atlantic Coast Conference), which had lost five in a row, rallied from a 13-point second-half deficit to pull off the improbable upset.
Syracuse (25-1, 12-1) travels to No. 5 Duke on Saturday night.
NO. 2 FLORIDA 71, AUBURN 66
In Gainesville, Fla., Patric Young made a pair of free throws with 19 seconds left and Auburn threw the ball away on the ensuing inbounds play, helping the second-ranked Gators to avoid a major upset.
With Syracuse losing, Florida could move in the top spot in college basketball for the first time since the 2006-07 season.
Young led the Gators (24-2, 13-0 Southeastern Conference) with 17 points and had seven rebounds.
Tahj Shamsid-Deen led Auburn (12-12, 4-9) with 17 points.
ARKANSAS 71, SOUTH CAROLINA 64
In Fayetteville, Ark., Michael Qualls and Coty Clarke led Arkansas past South Carolina.
Qualls had 20 points and Clarke had 12 points and 12 rebounds for the Razorbacks (18-9, 7-7 SEC).
Brenton Williams had 29 points for South Carolina (10-17, 3-11).
LOUISIANA STATE 92, MISSISSIPPI STATE 81
In Baton Rouge, La., freshmen Jarell Martin and Jordan Mickey combined for 39 points to lead Louisiana State (16-9, 7-6 SEC) over Mississippi State (13-13, 3-10).
Martin had a season-high 20 points. Mickey, who made a season-high 11 foul shots, finished with 19 points.
MISSOURI 67, VANDERBILT 64
In Columbia, Mo., Jordan Clarkson scored 21 points as Missouri held off Vanderbilt.
Earnest Ross added 16 points for the Tigers (19-7, 7-6 SEC).
Damian Jones had 19 points and seven rebounds for Vanderbilt (14-11, 6-7).
MIAMI 71, NOTRE DAME 64
In Coral Gables, Fla., Rion Brown had 21 points as Miami (13-13, 4-9 ACC) beat Notre Dame.
Pat Connaughton scored 22 points to lead the Irish (14-13, 5-9).