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Mitsunbu反应是有机合成中非常重要的一个反应，最常用的活化试剂就是三苯基膦（PPh3）和偶氮二甲酸二乙酯（DEAD）。经过多年的研究和发展，由底物醇出发形成了一大类合成应用，如醇的构型反转，成醚，成碳杂键，甚至形成新的碳碳键，称之为Mitsunobu 反应。这类反应被广泛应用在有机合成，特别是天然产物的合成中。 1994年，Tsunods等人首先报道了利用氰基亚甲基三正丁基膦（2-(Tributylphosphoranylidene)acetonitrile，CMBP）作为活化试剂用于Mitsunobu反应。【Tetrahedron Lett. 1994, 35, 5081–5082】 
CMBP作为活化试剂，在室温条件下反应产率由于经典的DEAD-TPP条件，但是效果不如TMAD-TBP条件。CMBP的优点是稳定性好，可以加热到100℃进行反应。 反应操作：氩气保护下，将醇 (1 mmol)和HA (1.5 mmol)溶于干燥的苯(5 mL，建议用甲苯代替)，加入CMBP (1.5 mmol)，加热至100℃反应24小时。浓缩，柱层析纯化。 反应机理 
Typical experimental procedure:1) (Cyanomethylene)tributylphosphorane (262 L, 1.00 mmol) was added to a solution of (tetrahydrofuran-3-yl)methanol (51 mg, 0.50 mmol) and 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (97 mg, 0.5 mmol) in degassed 1,4-dioxane (2 mL) sealed in a microwave tube at rt under nitrogen. The solution was heated to 150 °C for 30 min in the microwave reactor and cooled to rt.2) 1-Bromo-4-methoxybenzene (94 mg, 0.50 mmol), potassium carbonate (207 mg, 1.50 mmol) and [1,1'-Bis (diphenylphosphino)ferrocene]dichloropalladium(II) complex with CH2Cl2 (40.8 mg, 0.05 mmol) were added to the solution. The tube was sealed, evacuated and backfilled with nitrogen. Degassed water (1 mL) was added under nitrogen. The resulting mixture was stirred at 120 °C for 20 min. The reaction mixture was diluted with EtOAc (25 mL) and water (15 mL), the layers were separated, and the aqueous layer was extracted with EtOAc (15mL). The combined organic layers were washed with saturated brine (15 mL). The organic layer was dried with MgSO4, filtered and evaporated to afford the crude product. The crude product was purified by preparative HPLC (Waters XSelect CSH C18 ODB column, 5µ silica, 30 mm diameter, 100 mm length), using decreasingly polar mixtures of water (containing 1% by volume NH3OH (28-30% in H2O)) and MeCN as eluents to afford 4-(4-methoxyphenyl)-1-((tetrahydrofuran-3-yl)methyl)-1H-pyrazole (89 mg, 69 %) as a beige solid.【Tetrahedron Letters 2018，59，1708–1710】
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