Recent developments in gold-catalyzed cycloaddition reactions

Abstract

In the last years there have been extraordinary advances in the development of gold-catalyzed cycloaddition processes. In this review we will summarize some of the most remarkable examples, and present the mechanistic rational underlying the transformations.

Keywords: alkene; alkyne; allene; catalysis; cycloaddition; gold.

Scheme 1

AuCl₃-catalyzed benzannulations reported by Yamamoto.

Scheme 2

Synthesis of 9-oxabicyclo[3.3.1]nona-4,7-dienes from 1-oxo-4-oxy-5-ynes [40].

Scheme 3

Stereocontrolled oxacyclization/(4 + 2)-cycloaddition cascade of ketone–allene substrates [43].

Scheme 4

Gold-catalyzed synthesis of polycyclic, fully substituted furans from 1-(1-alkynyl)cyclopropyl ketones [45].

Scheme 5

Gold-catalyzed 1,3-dipolar cycloaddition of 2-(1-alkynyl)-2-alken-1-ones with nitrones [47].

Scheme 6

Enantioselective 1,3-dipolar cycloaddition of 2-(1-alkynyl)-2-alken-1-ones with nitrones [48].

Scheme 7

Gold-catalyzed 1,3-dipolar cycloaddition of 2-(1-alkynyl)-2-alken-1-ones with α,β-unsaturated imines [49].

Scheme 8

Gold-catalyzed (4 + 3) cycloadditions of 1-(1-alkynyl)oxiranyl ketones [50].

Scheme 9

(3 + 2) Cycloaddition of gold-containing azomethine ylides [52].

Scheme 10

Gold-catalyzed generation and reaction of azomethine ylides [53].

Scheme 11

Gold-catalyzed intramolecular (4 + 2) cycloadditions of unactivated alkynes and dienes [55].

Scheme 12

Gold-catalyzed preparation of bicyclo[4.3.0]nonane derivatives from dienol silyl ethers [59].

Scheme 13

Gold(I)-catalyzed intramolecular (4 + 2) cycloadditions of arylalkynes or 1,3-enynes with alkenes [60].

Scheme 14

Gold(I)-catalyzed intermolecular (2 + 2) cycloaddition of alkynes with alkenes [62].

Scheme 15

Metal-catalyzed cycloaddition of alkynes tethered to cycloheptatriene [65].

Scheme 16

Gold-catalyzed cycloaddition of functionalized ketoenynes: Synthesis of (+)-orientalol F [68].

Scheme 17

Gold-catalyzed intermolecular cyclopropanation of enynes with alkenes [70].

Scheme 18

Gold-catalyzed intermolecular hetero-dehydro Diels–Alder cycloaddition [72].

Figure 1

Gold-catalyzed 1,2- or 1,3-acyloxy migrations of propargyl esters.

Scheme 19

Gold(I)-catalyzed stereoselective olefin cyclopropanation [74].

Scheme 20

Reaction of propargylic benzoates with α,β-unsaturated imines to give azepine cycloadducts [77].

Scheme 21

Gold-catalyzed (3 + 3) annulation of azomethine imines with propargyl esters [81].

Scheme 22

Gold(I)-catalyzed isomerization of 5-en-2-yn-1-yl acetates [83].

Scheme 23

(3 + 2) and (2 + 2) cycloadditions of indole-3-acetates 41 [–86].

Scheme 24

Gold(I)-catalyzed (2 + 2) cycloaddition of allenenes [87].

Scheme 25

Formal (3 + 2) cycloaddition of allenyl MOM ethers and alkenes [90].

Scheme 26

(4 + 3) Cycloadditions of allenedienes [–98].

Scheme 27

Gold-catalyzed transannular (4 + 3) cycloaddition reactions [101].

Scheme 28

Gold(I)-catalyzed (4 + 2) cycloadditions of allenedienes [102].

Scheme 29

Enantioselective gold(I)-catalyzed (4 + 2) cycloadditions of allenedienes [88,102,104].

Scheme 30

(3 + 2) versus (2 + 2) Cycloadditions of allenenes [87,99].

Figure 2

NHC ligands with different π-acceptor properties [106].

Scheme 31

(3 + 2) versus (2 + 2) Cycloadditions of allenenes [106].

Scheme 32

Gold(I)-catalyzed intermolecular (4 + 2) cycloaddition of allenamides and acyclic dienes [109].