Table 1.

Optimization table for the Suzuki–Miyaura coupling reactions with porphyrin 13.

Entry	Catalyst/ligand SPhos (1 equiv)	Cat. mol % per C–Br	Base (24 equiv)	Temperature	Time	Boronic acid/ester (3 equiv per C–Br)	Yield % (porphyrin)
1	Pd2dba3/Sphos	6.25%	K3PO4	85 °C	48 h	14	32% (26)
2	Pd2dba3/Sphos	6.25%	K3PO4	85 °C	48 h	15	trace
3	Pd2dba3/SPhos	6.25%	K3PO4	110 °C	48 h	15	39% (27)
4	Pd2dba3/Sphos	6.25%	K3PO4	85 °C	48 h	16a	0
5	Pd2dba3/Sphos	6.25%	Cs2CO3	85 °C	48 h	16a	0
6	Pd2dba3/SPhos	6.25%	Cs2CO3	85 °C	48 h	16b	8% (30)
7	Pd2dba3/SPhos	6.25%	K3PO4	110 °C	48 h	17	48% (28)
8	Pd2dba3/SPhos	12.5%	K3PO4	110 °C	48 h	18a	0
9	Pd2dba3/SPhos	6.25%	Cs2CO3	85 °C	48 h	18b	72% (29)
10	Pd2dba3/Sphos	6.25%	K3PO4	85 °C	48 h	19	0
11	Pd2dba3/SPhos	6.25%	K3PO4	110 °C	48 h	19 a	trace
12	Pd2dba3/SPhos	12.5%	K3PO4	110 °C	24 h	20	25% (34)
13	Pd2dba3/SPhos	6.25%	Cs2CO3	110 °C	24 h	21	56% (33)
14	Pd2dba3/SPhos	6.25%	K3PO4	110 °C	48 h	23	trace
15	Pd2dba3/SPhos	6.25%	Cs2CO3	85 °C	48 h	23	trace
16	Pd(PPh3)4	10%	Na2CO3	100 °C	1 h	23 b	0
17	Pd2dba3/SPhos	6.25%	Cs2CO3	85 °C	24 h	23	trace
18	Pd2dba3/SPhos	6.25%	Cs2CO3	110 °C	24 h	23	trace
19	Pd2dba3/SPhos	25%	Cs2CO3	110 °C	24 h	23	16% (31)
20	Pd2dba3/SPhos	12.5%	Cs2CO3	110 °C	24 h	24	58% (35)
21	Pd2dba3/SPhos	6.25%	Cs2CO3	85 °C	24 h	25	47% (32)

^a5 equiv of boronic acid used in this reaction per C–Br. ^bMicrowave irradiation instead of conventional heating was used.