. 2020 Sep 21;5(38):24954–24963. doi: 10.1021/acsomega.0c03883

Table 1. Initial Screen of 2:1 EHA:Guanidinium Homoconjugate Catalyst Compositions and Related Control Reaction in Silanol Polycondensation^e.

entry	catalyst	M_n (Da)	M_w (Da)	Đ	conversion (%)	D4 (ppm)	HB⁺ pK_a²⁸^a
1	[TMG][EHA]₂	27,900	51,100	1.8	91	109	23.3
2	[^tBuTMG][EHA]₂	6800	10,700	1.6	61	70	25^b
3	[TBD][EHA]₂	3900	7200	1.8	33	118	26
4	[7MeTBD][EHA]₂	20,100	35,700	1.8	87	108	25.5
5	[G][EHA]₂	3900	6300	1.6	33	41
6	TMG	3000	4600	1.5	14	54
7	TBD	5900	9600	1.6	55	661
8	7MeTBD	7700	13,400	1.7	66	2310
9	EHA^c
10^d	LPNC	38,500	75,700	2.0	93	3668

pK_a values in MeCN.

pK_a value for MeTMG.

Did not polymerize.

Catalyst loading = 0.0013 mol %.

Reactions run with 5 g of silanol in capped 2 oz. vials at 110 °C for 2 h with magnetic stirring.

Table 1. Initial Screen of 2:1 EHA:Guanidinium Homoconjugate Catalyst Compositions and Related Control Reaction in Silanol Polycondensatione.