what is this, why are you worried, brush up with simple things, you will come out genius, learn with me, small drops of water make an ocean, you will be an expert in this
あなたが心配している理由は、これは簡単なことでブラッシュアップ、、何か、あなたは、天才が出てくる私と一緒に学ぶことが、水の小さな滴が海を作るには、この専門家になる
Name: 1,2-dimethoxymethane
C4H10O2
From the molecular formula, the compound has “0 degrees of unsaturation” (no double bonds or rings).
The 13C NMR has two peaks, a quartet at 
54 (a CH3) and a triplet at 80 (a CH2). Since the molecule has four carbons and only two 13C NMR peaks, there must be symmetry. Both peaks are in the regions where carbons next to electronegative atoms occur (oxygen).
τι είναι αυτό, γιατί είσαι ανήσυχος, βούρτσα με απλά πράγματα, θα βγει ιδιοφυΐα, να μάθουν μαζί μου, μικρές σταγόνες του νερού κάνει έναν ωκεανό, θα είστε ένας εμπειρογνώμονας σε αυτό
আপনি চিন্তিত কেন এই সহজ জিনিস নিয়ে ব্রাশ,, কি, আপনি, প্রতিভা বাইরে আসতে আমার সাথে শিখতে হবে, জলের ছোট ঝরিয়া একটি মহাসাগর না, আপনি এই একজন বিশেষজ্ঞ হতে হবে
C5H7O2N
From the molecular formula, the compound has “3 degrees of unsaturation” (3 double bonds or rings).
: ethyl cyanoacetate
The 13C NMR has 5 peaks, a quartet at 14 (a CH3), a triplet at 59 (a CH2), another triplet at 22 (another CH2), and two singlets, one at 118 and one at 172. Since the molecule has five carbons and five 13C NMR peaks, there must be no symmetry. The singlet at 172 is in the carbonyl region, most likely an acid or an ester. The CH2 at 59 is in the region where carbons next to electronegative atoms occur (i.e., oxygen) and the CH3 at 14 is a simple terminal methyl, suggesting an -O-CH2CH3 residue. The singlet at 118 would be consistent with a nitrile carbon and the shielded CH2 at 22 suggests that it may be adjacent to the sp-carbon of the nitrile
2-butanon-4-ene
The 13C NMR has 6 peaks, a quartet at 25 (a CH3), a triplet at 49 (a CH2), another quartet at 17 (another CH3), two doublets (a CH) , one at 124 and one at 131, and one singlet at 207. Since the molecule has six carbons and six 13C NMR peaks, there must be no symmetry. The singlet at 207 is in the carbonyl region, most likely an aldehyde or ketone. The CH3 groups at 17 and 25 are consistent with simple terminal methyl groups, with one slightly shifted by an mildly electronegative group (a carbonyl?). The doublets at 124 and 131 are in the alkene region, suggesting a -CH
CH- group. The remaining CH2 group at 49 is probably deshielded by two electronegative groups.
o que é isso, por que você está preocupado, retocar com coisas simples, você vai sair gênio, aprender comigo, pequenas gotas de água fazem um oceano, você vai ser um especialista neste
C8H8O
From the molecular formula, the compound has “5 degrees of unsaturation” (5 double bonds or rings).
acetophenone
The 13C NMR has 6 peaks, a quartet at 27 (a CH3), three doublets (CH groups), at 129, 128 and 133, and two singlets, one at 137 and one at 197. Since the molecule has eight carbons and six 13C NMR peaks, there must some degree of symmetry. The singlet at 197 is in the carbonyl region, most likely an aldehyde or ketone. The CH3 groups at 27 is consistent with a simple terminal methyl group, slightly shifted by an mildly electronegative group (a carbonyl?). The doublets at 129, 128 and 133 and the singlet at 137 are in the aromatic region, suggesting a monosubstituted aromatic group, with symmetry in four of the six carbons.
நீங்கள் கவலை ஏன் இந்த எளிய பொருட்களை கொண்டு துலக்க, என்ன, நீங்கள், மேதை வெளியே வர எனக்கு கற்று, நீர் சிறு துளிகள் ஒரு கடல் செய்ய, நீங்கள் இந்த ஒரு நிபுணர் இருக்கும்
के तपाईं चिंतित हो किन यो सरल कुरा संग ब्रश,, के हो, तपाईं, प्रतिभा बाहिर आउन मलाई संग सिक्न हुनेछ, पानी सानो थोपा एक महासागर बनाउन, तपाईं यस मा एक विशेषज्ञ हुनेछ\
તમને ચિંતા થતી હોય કે શા માટે આ સરળ બાબતો સાથે બ્રશ, શું છે, તમે પ્રતિભા બહાર આવે મારી સાથે શીખશે, પાણી નાના ટીપાં સમુદ્ર કરો, તો તમે આ એક નિષ્ણાત હશે
kas tas ir, kāpēc jūs uztraucaties, suka ar vienkāršām lietām, jūs iznākt ģēnijs, mācīties kopā ar mani, nelieli ūdens pilieni veikt okeānu, jums būs eksperts šajā
что это такое, почему ты беспокоишься, освежить с простых вещей, вы будете выходить гений, узнать со мной, маленькие капли воды сделать океан, вы будете экспертом в этом
cyclohexanon-2-ene
46, 30 and 41, two doublets (CH groups), at 129 and 145, and one singlet at 198. Since the molecule has six carbons and six 13C NMR peaks, there must be no symmetry. The singlet at 198 is in the carbonyl region, most likely an aldehyde or ketone. Two of the three CH2 groups are shifted by electronegative groups, suggesting a X-CH2-CH2-CH2-Y unit. The doublets at 129 and 145 are in the alkene region, suggesting a -CHCH- group. The three degrees of unsaturation suggests that the molecule also has a ring.
这是什么，你为什么担心，刷了简单的事情，你会出来的天才，学我，小水珠做出的海洋，你将在这方面的专家
- Electronegative groups are “deshielding” and tend to move NMR signals from attached carbons further “downfield” (to higher ppm values).
- The
![]()
-system of alkenes, aromatic compounds and carbonyls strongly deshield ![]()
![]()
C nuclei and move them “downfield” to higher ppm values. - Carbonyl carbons are strongly deshielded and occur at very high ppm values. Within this group, carboxylic acids and esters tend to have the smaller
![]()
values, while ketones and aldehydes have values ![]()
200.
-system of alkenes, aromatic compounds and carbonyls strongly deshield 
C nuclei and move them “downfield” to higher ppm values. 
200.
Simple interior (primary and secondary) carbons tend to be in the range 25 – 45. Methyl groups which terminate unbranched alkyl chains, however, are significantly shielded (moved to lower values), as shown by the examples above ( 14, 14.3 and 8.7). The origin of this effect is thought to be steric compression in the gamma (
) position due to gauche interactions. This is shown schematically below and the gamma position is marked above in the example for hexane.
The presence of an electronegative atom such as oxygen tends to move the chemical shift of the Œ-carbon down into the region 65 – 90, as shown in the examples below:
Halogens, however, have effects which are difficult to predict and carbons adjacent to halogens tend to have chemical shifts in the 30 – 50 region, as shown below. The effects are not simply additive, however, and multiple substitution can often be shielding (move the signal to lower values). The nitrile carbon is significantly shielding and adjacent carbons tend to occur in the 20 – 25 region.
Alkene carbons tend to have chemical shifts in the range 110 – 140, as shown in the examples below. Conjugation between alkene centers has little effect, as demonstrated by the two middle structures shown below. Conjugation with an oxygen, however, has a dramatic shielding effect, which is attributed to contributions from the resonance forms shown below.
Alkyne carbons occur in the region 65 -85, and are significantly shielding to the carbons which are immediately adjacent ( 1.5 for the terminal methyl of 2-pentyne).
Carbonyls are the most highly deshielded carbons which are typically encountered. Their intensity is usually weak, since there are no attached hydrogens to contribute to the Nuclear Overhauser Effect enhancement (with the exception of aldehydes). Typical chemical shifts occur in the region 170 – 210 with esters, carboxylic acids and amides at the low end, and simple ketones and aldehydes at the high end of the range.
Aromatic carbons have chemical shifts in the range 120 – 140 and are shifted within this range by the nature of the attached substituent. The multiplicity of aromatic peaks in the non-decoupled spectrum is useful for identifying aromatic substitution patterns.
THANKS AND REGARD’S
DR ANTHONY MELVIN CRASTO Ph.D
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