An operationally simple, fast and green synthesis of novel γ-hydroxyphosphonate and phosphine oxide derivatives

Figures & data

Table 1. Optimization of the reaction conditions.

Entry	Hydride reagent (equiv)	Solvent	Temp. (°C)	Time	Yield (%)^a
1	LiAlH4 (0.25)	THF	0–25	2 h	0
2	NaBH4 (1)	EtOH	25	12 h	30
3	NaBH4 (3)	EtOH	25	5 h	65
4	NaBH4(3)/Al2O3(12)	Solvent-free^b	25	5 min	90

^aIsolated yield.

^bThe reaction was performed in solvent-free conditions but in the presence of few drops of MeOH as protonating agent.

Table 2. Substrate scope studies.

Entry	R^1	R^2	R^3	R^4	Product	%(maj/min)^b	Yield (%)^c
1	EtO	H	Ph	Me	2a	61/39	90
2	EtO	H	2-thienyl	Me	2b	84/16	85
3	EtO	H	Ph	Ph	2c	65/35	90
4	Ph	H	2-furyl	Me	2d	54/46	85
5	Ph	H	2-thienyl	Me	2e	62/38	88
6	Ph	H	Ph	Me	2f	52/48	87
7	Ph	H	Ph	Ph	2g	92/08	93
8	EtO	Me	Me	Me	2h	–	91
9	MeO	Me	Me	Me	2i	–	86
10	Ph	Me	Me	Me	2j	–	90

^a5 drops of MeOH for 1 mmol of substrate 1.

^bDetermined from the ³¹P NMR spectra.

^cIsolated yield.