Nature Communications

Table 1 Screening and optimization^a

From: Asymmetric α-allylic allenylation of β-ketocarbonyls and aldehydes by synergistic Pd/chiral primary amine catalysis


Entry	Amine	L	Additive	Solvent	Yield (%)^b		Dr^c	Ee (%)^d
1	(S)-A0	L1	/	DCE	47	2/1		85
2	(S)-A1	L1	/	DCE	51	2/1		90
3	(S)-A2	L1	/	DCE	22	2/1		92
4	(S)-A1	(S)-L2	/	DCE	15	2/1		58
5	(S)-A1	(S)-L3	/	DCE	23	1/1		28
6	(S)-A1	(S)-L4	/	DCE	51	6/1		98
7	(S)-A1	(R)-L4	/	DCE	39	1/2		56
8	(S)-A1	(race)-L4	/	DCE	41	4/1		92
9	(S)-A1	(S)-L5	/	DCE	trace	9/1		>99
10	(S)-A1	(S)-L6	/	DCE	6	2/1		89
11	(S)-A1	(S)-L7	/	DCE	n.r.	/		/
12^e	(S)-A1	(S)-L4	NaBAr^F₄	DCE	57	6/1		98
13	(S)-A1	(S)-L4	NaBAr^F₄	DMSO	7	3/1		96
14	(S)-A1	(S)-L4	NaBAr^F₄	THF	12	2/1		87
15	(S)-A1	(S)-L4	NaBAr^F₄	toluene	17	3/1		93
16	(S)-A1	(S)-L4	NaBAr^F₄	MeOH	n.r.	/		/
17	(S)-A1	(S)-L4	NaBAr^F₄	EA	63	12/1		>99
18^f	(S)-A1	(S)-L4	NaBAr^F₄	EA	62	>20/1		>99
19^g	(S)-A1	(S)-L4	NaBAr^F₄	EA	74	>20/1		>99

^aReaction conditions, unless otherwise noted: 1a (0.1 mmol), 2a (0.2 mmol), Pd₂(dba)₃ (5 mol %), Ligand (10 mol %), amine* (20 mol%), and additive (12 mol%) in 1,2-dichloroethane (DCE, 0.3 mL) at 40 °C for 24 h.
^bIsolated yield of all diastereoisomers; n.r. = no reaction.
^cDr values were determined by ¹HNMR analysis.
^dThe ee values were determined by chiral HPLC analysis of the alcohol derivative of the product.
^eNaBAr^F₄ (Ar^F = 3, 5-(CF₃)₂Ph) as a promoting additive.
^fPd(PPh₃)₄ instead of Pd₂(dba)₃.
^gNHTf₂ instead of TfOH.

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