DOMINO REACTIONS IN LIBRARY SYNTHESIS - Diversity-Oriented Synthesis - page 151

SCHEME 5.8 Three-component/triple domino synthesis of pyrrolo[3,4- b ]pyridin-5-ones
23 .

TABLE 5.5 Pyrrolopyridines 23 Derived from a Three-Component/Triple Domino
Reaction Sequence

Entry R 1 R 2 R 3 R 4 Yield (%) a

1 n -Hex 2-[3 ,4 -OMe) 2 ]Ph(CH 2 ) 2 Bn CO 2 Et 23a ,58

2 n -Pr 4-OMe-Bn Bn CO 2 Et 23b ,57

3 n -Pr 3,5-(OMe) 2 -Bn Bn CO 2 Et 23c ,68

4 c -Oct 4-F-Bn Bn CO 2 Et 23d ,66

5 n -Pr 3,4-dioxolanyl-Ph Bn CO 2 Et 23e ,58

2-[3 ,4 -OMe) 2 ]Ph(CH 2 ) 2 6 n -Hex Bn 4-NO 2 -Ph 23f ,63

2-[3 ,4 -OMe) 2 ]Ph(CH 2 ) 2

7 n -Hex Bn 4-OMe-Ph 23g ,55

8 n -Hex n -Bu i -Pr 4-NO 2 -Ph 23h ,59

a Isolated yields.