Identify the following compound from its ir and proton nmr spectra. c4h6o: nmr: δ 2.43 (1h, t, j = 2 hz); δ 3.41 (3h, s); δ 4.10 (2h, d, j = 2 hz) ir: 2125, 3300 cm–1 the c4h6o compound liberates a gas when treated with c2h5mgbr

The structure of the compound is in attachment. The name of the compound is3-Methoxy prop-1-yne.

Explanation:

The  NMR data which is available to us is the following:

The first NMR signal appears   at 2.4 ppm(parts per million) and this peak has a triplet  spin multiplicity . This NMR signal is due to the proton present on terminal alkyne as it appears very high field frequency as the hydrogen is shielded on account of magnetic anisotropy. There is a cylindrical electron density which is available along  the axis in acetylene molecule and when external magnetic field is applied this cylindrical electron density along the axis will try to orient with the magnetic field and will move cylindrically around the  molecule and this would shield the proton present on terminal alkyne labelled as 1 in structure.

The triplet multiplicity of this proton occurs on account of long ranging coupling with CH₂ protons available on the carbon next to the alkyne bond.

The second NMR  signal appears at 3.41 PPM and this occurs on account the CH₃ protons labelled as 3 in structure. The shift for this proton is shifted slightly downfield as it is attached directly with the electronegative Oxygen atom which deshields the proton. The spin multiplicity for this proton is singlet as it is evident in the structure as it does not have any neighbouring protons.

The third NMR signal appears at 4.10 ppm is due to the CH₂ protons labelled as 2 in the structure . This proton is even more deshielded as it is directly attached to the oxygen atom as well as to sp hybridized carbon atom. so this proton is even more deshielded and appears more down field at 4.10 ppm.The spin multiplicity for this proton is doublet as it undergoes a long-range coupling with the proton available at terminal alkyne indiated as 1 position in the structure

Kindly refer the attachment for structure.

The gas produced could be ethane gas as the terminal proton available at alkyne is acidic in nature and C₂H₅MgBr being a carbanion can abstract it leading to formation of ethane(C₂H₆) and magnesium salt of alkyne.

the answer is either b or c