Entry

Initial Iminophosphorane

Indolizine formed

Yield (%)^a

1

Ethyl (Z)-3-(thiophen-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (1)

19, 20

76

2

Ethyl (Z)-3-(thiophen-3-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (2)

21, 22

82

3

Ethyl (Z)-3-(4-methylthiophen-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (3)

23, 24

70

4

Ethyl (Z)-3-(4-bromothiophen-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (4)

25, 26

80

5

Ethyl (Z)-3-(4-phenylthiophen-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (5)

27, 28

78

6

Ethyl (Z)-3-(5-phenylthiophen-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (6)

29, 30

81

7

Ethyl (Z)-3-(furan-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (7)

31, 32

62

8

Ethyl (Z)-3-(4-phenylfuran-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (8)

33, 34

62

9

Ethyl (Z)-3-(1-methyl-1H-pyrrol-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (9)

35, 36

51

10

Ethyl (Z)-3-(1-benzyl-1H-pyrrol-2-yl)-2-((triphenyl-λ⁵-phosphaneylidene)amino)acrylate (10)

37

48