Final, IR and NMR Flashcards
Give a frequency and description of the IR spectrum of C-C
Around 1000 (not really used)
Give a frequency and description of the IR spectrum of C=C
Around 1660
Small-medium intensity
Give a frequency and description of the IR spectrum of C≡C
Around 2150
Small-Medium Intensity with sharp peaks
Give a frequency and description of the IR spectrum of C-H (sp3)
Less than 3000
Give a frequency and description of the IR spectrum of C-H (sp2)
Greater than 3000
Give a frequency and description of the IR spectrum of C-H (sp)
Greater than 3000
Give a frequency and description of the IR spectrum of C=O
Around 1700
Very high intensity, dominating the spectrum
Give a frequency and description of the IR spectrum of C-O
Around 1200
Less than C=O due to single bond
Give a frequency and description of the IR spectrum of O-H
Huge range from 3500-3600
Dilute will be higher, very broad peak
Give a frequency and description of the IR spectrum of N-H
Range from 3500-3300
N has less EN-> smaller wavenumbers
Give a frequency and description of the IR spectrum of C≡N
Around 2250
Small-Medium Intensity Peaks that are relatively sharp
How many peaks will Primary, Secondary, and Tertiary Amines have in the N-H range?
two, one, or zero
What vibrational frequency is around 2250 and has peaks that are small-medium intensity that are relatively sharp?
C≡N
What vibrational frequency is around 1200?
C-O
What vibrational frequency is around 3000+?
C-H sp2 and sp
What vibrational frequency is around 2150 with small-medium intensity sharp peaks?
C≡C
What vibrational frequency is around 1700 and has very high intensity peaks dominating the spectrum?
C=O
What vibrational frequency is around 3000-?
C-H sp3
What vibrational frequency is around 3500-3600 and has a very broad peak?
O-H
What vibrational frequency is around 1660 and has small-medium intensity peaks?
C=C
What does the number of signals in an NMR spectrum tell you?
how many different protons or carbons you have
What does the position of signals in an NMR spectrum tell you?
The position of the signals tells you their environment (electron density)
Lower chemical shift values are called more ‘upfield’ and are shielded by electrons
Higher chemical shift values are called more “downfield” and are deshielded by close proximity to an electronegative group such as a halogen
What does the area under a signal in an NMR spectrum tell you?
number of protons/carbons per signal
What does the multiplicity of a signal in an NMR tell you?
the number of protons or carbons less than three bonds away from the one being measured
N neighbors of magnetically equivalent protons/carbons + 1
Four and Three is a CH2CH3
What is the typical HMNR chemical shift for 1* to 3* Alkyl? (Small scale)
1 to 2
What is the typical HMNR chemical shift for ketones? (Small scale)
2-2.5
What is the typical HMNR chemical shift for aromatic groups? (Small scale)
7ish
What is the typical HMNR chemical shift for aldehydes? (Small scale)
around 10
What is the typical HMNR chemical shift for carboxylic groups? (Small scale)
10-13
What is the typical CMNR chemical shift for aldehydes and ketones? (Large scale)
180-215
What is the typical CMNR chemical shift for esters and carboxylic acids? (Large scale)
160-185
What is the typical CMNR chemical shift for Aryl Carbons? (Large scale)
100-170
What is the typical CMNR chemical shift for 1* to 3* Alkyls? (Large scale)
0-50
