Table 3. Synthesis of difluorocyclopropyl allyl alcohols 17a–h from aldehydes 12a–h ^a .

Entry	R1	x	13	15		17
			Yield b (%)	Conv. c (%)	Yield b (%)	Yield b (%)
1	2-Furyl	a	82	66	40	94
2	Ph	b	—	28 d	—	—
3			—	29 d , e	n.d. f	—
4			73	37	n.d. f	—
5	2-Thiophenyl	c	98	77	71	50
6	5-Benzo[d][1,3]-dioxole	d	94	50	43	75
7	2-Pyridyl	e	87	0	—	—
8	2-N-Boc-pyrrolyl	f	60	92	54	6
9	2-Thiazolyl	g g	74 h	0	—	—
10	3-Me-2-furyl	h i	45 j	80	45	84

^a Conditions: (i) (carbethoxymethylene)triphenylphosphorane (1.1–1.3 eq.), DCM, r.t., 6–20 h (ii) MDFA (2.5 eq.), TMSCl (2.5 eq.), KI (2.8 eq.), diglyme (1.17 eq.), 120 °C, 4 h (iii) DIBAL (3 eq.), toluene or DCM, –78 °C to r.t., 8 h.

^b Isolated yields.

^c Determined by ¹H NMR.

^d Reaction time of 24 h.

^e Starting from commercial ethyl cinnamate 13b.

^f 13b and 15b were inseparable via column chromatography or distillation.

^g Aldehyde 12g was synthesised from thiazole and used crude in the olefination reaction (see ESI for details).

^h Calculated over two steps from thiazole, 4 : 1 mixture of E : Z-isomers.

ⁱ Aldehyde synthesised in situ from the oxidation of 2-hydroxymethyl-3-methyl furan (see ESI for details).

^j Calculated over two steps from methyl 3-methyl-2-furoate.