Combining catalysts having different or similar properties is currently an important topic in catalysis development.[1] Various catalyst combinations, such as Lewis acid/Brønsted base,[2] Lewis acid/Lewis base,[3, 4] Lewis acid/Brønsted acid,[5] Lewis acid/Lewis acid,[5] and transition metal/Lewis acid [6] have been developed to provide unique catalytic activities. Herein we describe a different class of combination catalysts, in which Brønsted ...