重氮盐参与的Heck 反应

芳基重氮盐可以发生的反应最常见的就是Sandmeyer反应可以制备卤代芳烃，芳基酚或芳基腈，另外就是Balz-Schiemann反应制备芳基氟化物，偶氮偶合反应制备偶氮二芳基类化合物。1995年Beller等人报道了利用重氮盐作为底物进行Heck反应制备芳基烯基化物，这是一种很实用的制备芳基烯烃的反应，此类反应不需要膦催化剂和胺，条件温和。

反应实例（Beller,M.; Kuehlein, K. Synlett. 1995, 441）

^a The Palladium is 5% of weight on the correspondingcatalyst support. ^b 2-EH = 2-ethylhexan-1-ol. ^c Already used catalyst.

Generalprocedure for the synthesis of cinnamic acid esters:

30 mmol of corresponding diazonium salt and 60 mmol of acrylic acid esterare suspended in 40 mL of the solvent. Subsequently, 0.6 mmol of palladium on activatedcharcoal (5% weight) is added at 0°C.Then the reaction mixture is heated to 60°C in the course of 1 hour and stirred for 12 hoursat this temperature. After cooling to room temperature, the catalyst isfiltered off and washed with the solvent. The solvent is evaporated in vacuoand the crude product is further purified by crystallized or chromatography onsilca.