Pericyclic MBFTs

Pericyclic reactions, such as Diels-Alder cycloaddition, electrocyclic reactions, and ene reactions, are extremely effective tools in constructing complex products [18]. 

Especially when combining two or more pericyclic reactions with each other, the outcome is highly efficient and could be almost qualified as miraculous, as each cycloaddition event could introduce a new ring, two new covalent bonds, and up to four new contiguous asymmetric centers in one step. Moreover, great progress has been achieved in the intramolecular and asymmetric pericyclic reactions recently, which provide highly effective approaches for the rapid elaboration of complex polycyclic systems. Some prominent total syntheses achieved based on pericyclic MBFTs will be exemplified below. 

In 2009, the group of MacMillan documented a new organocatalytic Diels-Alder/amine cyclization sequence, which allowed rapid and enantioselective 

In 2013, the group of Liu reported the first total synthesis of bolivanine through a Diels-Alder/intramolecular hetero-Diels-Alder cascade sequence, which allowed 

---

The goal of this chapter is to highlight and discuss a selection of MBTFs employed in the total synthesis of natural products during the past 10 years. As MBTFs usually involve many distinct steps, which make it hard to classify them, this chapter is divided into five parts anionic-initiated MBFTs, cationic-initiated MBFTs, radical-mediated MBFTs, pericyclic MBFTs, and transition-metal-catalyzed MBFTs, hoping that the division can help show the MBFTs employed in the synthesis of natural products clearly and concisely. 

This chapter summarized the application of MBFTs, including electrophilic, nucleophilic, transition-metal-catalyzed, pericyclic, and radical pathways, in the... 

---